Answer:
a commutator
Explanation:
(b) Calculate the momentum when a mass of 40kg is moving with a velocity of 20m/s in the forward
direction.
Explanation:
momentum = mass x velocity
momentum = 40 x 20 = 800kgm/s
Answer:
800kgm/s
Explanation:
momentum= mass×velocity
= 40×20
= 800kgm/s
A carpenter measured the lengeth of a small piece of timber as 24.6cm .Calculate the relative error in the measurement if the true length is 24.5cm
ANSWER:
0.4081%
Explanation:
Difference=24.6-24.5=0.1
Relative error = 0.1/24.5*100=0.4081%
Relative error is equal to the = difference between both the values/The true value *100
(b) 360 days into seconds.
Sec
(c)
(d) A body has weight 60
0 N on the surface of the mars then what is its mass on the
[Ans: 157.89 kg)
What is weight of a body of mass 100 kg on the surface of the moon? [Ans: 166N]
Explanation:
(b) We know that,
1 day = 24 hours
1 hour = 3600 s
So, we found that, 1 day = 86400 s
We need to find the 360 days into seconds. So,
1 day = 86400 s
360 days = 86400×360
360 days = 31104000 seconds
(d) Weight of a body, W = 600 N
Acceleration due to gravity on mars is 3.7 m/s²
Weight, W = mg
m is mass of body
[tex]m=\dfrac{W}{g}\\\\m=\dfrac{600}{3.7}\\\\m=162.16\ kg[/tex]
(e) Mass of body, m = 100 kg
Acceleration due to gravity on the moon, 1.6 m/s²
Weight, W = 100 × 1.6
W = 160 N
What are the signs of the velocity, force, and acceleration (components) afterthe cart is released and is moving qway from the motion sensor? (The positive xdirection is toward the motion sensor, to the right.
Answer:
car is moving away its direction is negative.
the speed must also be negative.
speed this distance decreases the acceleration is negative and if the speed is increasing the acceleration is positive.
Explanation:
In the exercise they indicate that the direction to the motion sensor is positive, as they indicate that the car is moving away its direction is negative.
The speed of the car is
v = (x₂-x₁) / t
As the positions are negative, and the car moves away the speed must also be negative.
The analysis for acceleration must be very careful if the speed this distance decreases the acceleration is negative and if the speed is increasing the acceleration is positive.
What happens when white light shines through a translucent, red, glass window? a) All colors of light except red are transmitted through the glass. b) Red light is transmitted through and reflected by the glass c) Red light is absorbed by the glass d) all colors except red are reflected by the glass
Answer:
b. Red light is transmitted through and reflected by the glass
Explanation:
Give me brainliest plz!
All of the wavelengths of the red light are absorbed when it passes through a translucent red glass window, but the red light is transmitted and reflected.
What happens when white light shines through red glass?Red light emerges from the other side of a white light source that has been passed through a red filter. This is so that only red light can pass through the red filter. The spectrum's other colors (wavelengths) are absorbed. Similar to this, a green filter only lets through green light.White light is colorless light that contains all the wavelengths of the visible spectrum. Only specific wavelengths of white light are filtered through transparent or translucent things.Through a colorful glass, white light shines through. Except for the color it is shining through, all light wavelengths are absorbed by the glass.Therefore, if the red light passes through a translucent, red, glass, window, all the wavelengths are absorbed but the red light is transmitted and reflected.
Therefore, the correct answer is option b) Red light is transmitted through and reflected by the glass.
To learn more about light refer to:
https://brainly.com/question/12002703
#SPJ2
(c) An object of mass 100 kg is accelerated uniformly from a velocity of 15m/s to 20 m/s in 10 s.
Calculate the initial and final momentum of the object.
Also, find the magnitude of the force exerted on the object.
Explanation:
momentum = mass x velocity
initial momentum = 100 x 15 = 1500kgm/s
after momentum = 100 x 20 = 2000kgm/s
a =(v-u)/t
a = (20-15)/10
a = 5/10
a = 0.5m/s²
f = ma
f = 100 x 0.5
f = 50N
During a collision with another car, the occupants of a minivan initially travelling at 4.0 m/s come to a complete stop in 0.5 s. What was the acceleration of the occupants of the minivan?
a) 8.0 m/s2
b) –8.0 m/s2
c) 2.0 m/s2
d) –2.0 m/s2
Answer: b) - 8.0 [tex]m/s^{2}[/tex]
Explanation: Acceleration is a vector indicating a rate an object's velocity changes over time:
a = [tex]\frac{v}{t}[/tex]
and its SI unit is [tex]m/s^{2}[/tex]
For the minivan to stop, it takes a period of 0.5s:
a = [tex]\frac{4.0}{0.5}[/tex]
a = 8.0 [tex]m/s^{2}[/tex]
As a vector, acceleration has magnitude (8[tex]m/s^{2}[/tex]) and direction. Since it is stopping, the minivan has a direction opposite to the other car, which means acceleration is negative. So: a = [tex]- 8.0 m/s^{2}[/tex].
1. A uniform magnetic field is directed vertically upwards. In which direction in this field should an alpha particle be projected so that it is deflected south ward? Name and state the rule you have used to find the direction in this case.
Answer:
1. Fleming's left hand rule
2. It must be projected towards the east
Explanation:
Fleming's left-hand rule states that; When a current-carrying conductor is placed in an external magnetic field, the conductor experiences a force perpendicular to both the field and to the direction of the current flow. This rule was first put forward by John Ambrose Fleming in the later part of the nineteenth century.
Hence if the thumb, fore finger and middle finger of the lefthand are held mutually at right angles to each other; the thumb shows the direction of motion, the fore finger shows the direction of the field while the middle finger shows the direction of the current.
Hence, if the alpha particle is projected eastwards(at right angles) to the uniform magnetic field, it will be deflected southwards in the magnetic field.
One solution to minimize resonance with buildings is to ______ the width to span ratio.
Answer:
Increase
Explanation:
Resonance is a phenomenon which occurs when a body A in motion set another body B into motion of it own natural frequency. So for resonance to be minimize in a body is to increase the width to span ratio. So as to reduce the overall vibration which affects directly building resonance, the stiffness or trusses and girders should be increase. The increase in this aspect helps to reinforce building structure and support.
# A cheetah can start from rest and attain the velocity 72km/h in 2 seconds. Calculate the acceleration of cheetah
Answer:
[tex]10 \: [/tex] m/s ^2Explanation:
Solution,
When a certain object comes in motion from rest, in the case, initial velocity = 0 m/s
Initial velocity ( u ) = 0 m/s
Final velocity ( v ) = 72 km/h ( Given)
We have to convert 72 km /h in m/s
[tex]72 \: km \: per \: hour[/tex]
[tex] = 72 \times \frac{1000}{60 \times 60} [/tex]
[tex] = 20 [/tex] m/s
Final velocity ( v ) = 20 m/s
Time taken ( t ) = 2 seconds
Acceleration (a) = ?
Now,
we have,
[tex]a = \frac{v - u}{t} [/tex]
[tex]a = \frac{20 - 0}{2} [/tex]
[tex]a = \frac{20}{2} [/tex]
[tex]a = 10 [/tex] m/s ^2
Hope this helps...
Good luck on your assignment..
help me its emergency I need a correct answer please if you don't know then please dont guess
Answer:
True.
Explanation:
Total internal reflection is bound to occur when light travels from dense medium to less dense.
From the table given in the question above, we obtained:
Refractive Index of Crown glass = 1.52
Refractive Index of Asphalt = 1.635
From the above, Crown glass has a lower refractive index when compared to Asphalt. This means that Crown glass is less dense than Asphalt.
Therefore, total internal reflection will not occur when light travels from Crown glass to Asphalt because Crown glass is less dense than Asphalt.
= 21000
19
20
= 19,950
TRY THESE
Amachinery worth 10.500 depreciated by 5% Find its value after one year
Find the population of a city after 2 years, which is at present 12 lakh, if the rate
of increase is 49
6
M
EXERCISE 8.3
Calculate the amount and compound interest on
원
(a) * 10,800 for 3 years at 12% per annum compounded annually.
125%
18,000 for 2 years at 10% per annum compounded annually.
(c) 62,500 for 12 years at 8% per annum compounded half yearly.
(d) *8,000 for 1 year at
at 9% per annum compounded half yearly.
(You could use the year by year calculation using SI formula to verify).
(e) $10,000 for 1 year 48% per annum compounded half yearly.
from Bant to buy a conter at a rate of 15% pa
On a 100km track , a train travels the first 30km with a speed of 30km/h . How fast the train travel the next 70 km if the average speed for the entire journey is 40km/h?
Answer:
v = 46.67 km/h
Explanation:
We will use the following formula throughout this numerical:
s = vt
where,
s = distance covered
v = speed
t = time taken
FOR FIRST 30 km:
s = 30 km
v = 30 km/h
t = t₃₀ = ?
Therefore,
30 km = (30 km/h)(t₃₀)
t₃₀ = (30 km)/(30 km/h)
t₃₀ = 1 h
FOR TOTAL 100 km:
s = 100 km
v = 40 km/h (Average Speed)
t = total time = ?
Therefore,
100 km = (40 km/h)(t)
t = (100 km)/(40 km/h)
t = 2.5 h
FOR LAST 70 km:
s = 70 km
t₇₀ = t - t₃₀ = 2.5 h - 1 h = 1.5 h
v = v₇₀ = ?
Therefore,
70 km = v(1.5 h)
v = 70 km/1.5 h
v = 46.67 km/h
What is an electron?
A. A negative particle inside the nucleus
B. A negative particle outside the nucleus
C. A positive particle inside the nucleus
D. A particle inside the nucleus that has no charge
Answer:
B. A negative particle outside the nucleus
Explanation:
Electrons are very small particles orbiting outside of the nucleus of an atom. They carry negative charges.
The nucleus only contains protons and neutrons. Protons are positive, and neutrons have no charge (i.e. neutral)
A refrigerator recieves 240 V of electricity. If it use 32 A of current, what is the resistance of the refrigerator?
Answer:
7.5 Ω
Explanation:
Voltage = Current x Resistance
(V = IR)
240 = 32 R
R = 240 / 32
= 7.5 Ω
A small pollutant particle falls to the ground through the air at rest with a speed limit of 0.3 mm / s. The particle has a mass of 10 ^ -10 g and the drag force is of the form bv. What is the value of b?
Answer:
3.3×10⁻⁹ kg/s
Explanation:
There are two forces on the particle: weight force pulling down and drag force pushing up. At terminal velocity, the speed is constant, so the acceleration is zero.
∑F = ma
bv − mg = 0
b = mg / v
b = (10⁻¹³ kg) (9.8 m/s²) / (3×10⁻⁴ m/s)
b = 3.3×10⁻⁹ kg/s
Somebody help!?
13. The graph below represents the speed of a car vs. time. Circle the letter(s) with the lowest acceleration.
What is the acceleration? How do you know?
Answer:
acceleration is the rate of change of the velocity of an object with respect to time. Accelerations are vector quantities. The orientation of an object's acceleration is given by the orientation of the net force acting on that object.
Explanation:
Calculating acceleration involves dividing velocity by time — or in terms of SI units, dividing the meter per second [m/s] by the second [s]. Dividing distance by time twice is the same as dividing distance by the square of time. Thus the SI unit of acceleration is the meter per second squared .
A wave travels at 295 m/s and has a wavelength of 2.50 m. What is the frequency of the wave?
O 118 Hz
O 292 Hz
O297 Hz
O 738 Hz
Answer:
[tex]118\; \rm Hz[/tex].
Explanation:
The frequency [tex]f[/tex] of a wave is equal to the number of wave cycles that go through a point on its path in unit time (where "unit time" is typically equal to one second.)
The wave in this question travels at a speed of [tex]v= 295\; \rm m\cdot s^{-1}[/tex]. In other words, the wave would have traveled [tex]295\; \rm m[/tex] in each second. Consider a point on the path of this wave. If a peak was initially at that point, in one second that peak would be
How many wave cycles can fit into that [tex]295\; \rm m[/tex]? The wavelength of this wave[tex]\lambda = 2.50\; \rm m[/tex] gives the length of one wave cycle. Therefore:
[tex]\displaystyle \frac{295\;\rm m}{2.50\; \rm m} = 118[/tex].
That is: there are [tex]118[/tex] wave cycles in [tex]295\; \rm m[/tex] of this wave.
On the other hand, Because that [tex]295\; \rm m[/tex] of this wave goes through that point in each second, that [tex]118[/tex] wave cycles will go through that point in the same amount of time. Hence, the frequency of this wave would be
Because one wave cycle per second is equivalent to one Hertz, the frequency of this wave can be written as:
[tex]f = 118\; \rm s^{-1} = 118\; \rm Hz[/tex].
The calculations above can be expressed with the formula:
[tex]\displaystyle f = \frac{v}{\lambda}[/tex],
where
[tex]v[/tex] represents the speed of this wave, and [tex]\lambda[/tex] represents the wavelength of this wave.Answer:
118
Explanation:
1. Analogies exist between rotational and translational physical quantities. Identify the rotational term analogous to each of the following: acceleration, force, mass, work, translational kinetic energy, linear momentum, impulse.
2. Explain why centripetal acceleration changes the direction of velocity in circular motion but not its magnitude.
Answer:
1) a α, m I, W=F.d W =τ . θ,
2) a = v²/r
Explanation:
1) The amounts of rotational and translational motion are related
acceleration is
a = d²x / dt²
linear displacement is equivalent to angular rotation, therefore angular acceleration is
α = d²θ / dt²
force in linear motion is equivalent to moment in endowment motion
F = m a
τ = I α
the mass is the inertia of the translation, in rotational motion the moment of inertia is the rotational inertia
I = m r²
Work is defined by W = F. d
in rotation it is defined by W = τ . θ
The linear momentum is p = mv
the angular momentum L = I w
momentum the linear motion is I = F dt
in the rotation it is I = τ dt
2) The velocity is a vector therefore it has modulus and direction, linear acceleration changes the modulus of velocity, whereas circular motion changes the direction (the other element of the vector).
[tex]a_{c}[/tex]Ac = v²/r
A stone is dropped from a height of 49m and simultaneously another ball is thrown upward from the ground with a speed of 40m/s. when and where do the two stone meet
Answer:
S1 = 1/2 g t^2 distance stone falls in time t
S2 = Vy t - 1/2 g t^2 distance thrown stone rises in time t
H = 49 = S1 + S2 = Vy t
t = 49 / 40 sec time when stones meet
Check:
Stone 1 falls: 1/2 g t^2 = 1/2 * 9.8 * (49 / 40)^2 = 7.35 m
Stone 2 rises : 40 * (49 / 40) - 1/2 * 9.8 (49 / 40)^2 = 41.65 m
Write the equation for simple harmonic motion (x-t),(v-t), and find v at t=2s and t=3s if the object is initially at the right extreme of origin and moving in the negative x-direction. (A=2cm, T=8s)
Answer:
Explanation:
T = 8 s
angular frequency ω = 2π / T
= 2 π / 8
= π / 4
x ( t ) = A ( sinωt + π / 2 ) because initial phase difference is π / 2
= A cos ωt
= A cos π t / 4
v = Aω sinωt
= 2 x π / 4 sinωt
= .5 π sinπt / 4
when t = 2
v = .5 π sinπ x 2 / 4
= .5 π x 1
= 1.57 cm /s
At t = 3 s
v = .5 π sin π x 3 / 4
= .5 π sin 135°
= .5 π / √ 2
= 1.11 cm /s
A railroad car having a mass of 15 Mg is coasting at 1.5 m/s on a horizontal track. At the same time another car having a mass of 12 Mg is coasting at 0.75 m/s in the opposite direction. If the cars meet and couple together, determine the speed of both cars just after the coupling. Find the difference between the total kinetic energy before and after coupling has occurred. Explain qualitatively what happened to this energy.
Answer:
Explanation:
We shall apply law of conservation of momentum to know velocity after collision . Let it be v .
total momentum before collision = total momentum after collision
15 x 1.5 - 12 x .75 = ( 15 + 12 ) v
v = .5 m /s
kinetic energy before collision
1/2 x 15 x 1.5² + 1/2 x 12 x .75²
= 16.875 + 3.375
= 20.25 J
kinetic energy after collision
= 1/2 x ( 15 + 12 ) x .5²
= 3.375 J
Loss of energy = 16.875 J
This energy appear as heat and sound energy that is produced during collision .
Pink
Green
Red
Black
Blue
Yellow
Orange
"Milk colour"
what planet colour is that ??
thankyou for helping
Answer:
Pink - Pluto
Green - Mercury
Red - Mars
Black - Saturn
Blue - Neptune
Yellow - Jupiter
Orange - Jupiter
Milk Color - Venus
Explanation:
The galaxy is full of colors. There are various planets in the galaxy which are different colored. Their color is usually determined by the gases present there. The pink gases present near the Pluto makes Pluto appears to be of magenta or pink colored. The mercury is green colored because it reflects green rays. Mars is called the Red planet because of presence of Martin Rocks there.
advantages of cutting crops with sickle ? please friends give this answer in easy way....
Answer: The only advantage cutting crops with a sickle is that its very effective for cutting lodged crops.
I need help asap please please
a light ray strikes at a plane mirror at an angle of incident of 35 degree what would the angle of reflection be explain???
laws of reflection
I = r
angle of incident = angle of reflection
35 = 35
What does addition of two vectors give you?
Answer:
Explanation:
To add or subtract two vectors, add or subtract the corresponding components. Let →u=⟨u1,u2⟩ and →v=⟨v1,v2⟩ be two vectors. The sum of two or more vectors is called the resultant. The resultant of two vectors can be found using either the parallelogram method or the triangle method .
on heating gases expand ______________ than solids and liquids
Answer:
On heating gases expands than solid and liquid because the molecules gets seperated and the volume increases that causes to expand.
Explanation:
Hope it is helpful
please mark me as brainliest
please
4. Going back to the dog whistle in question 1, what is the minimum riding speed needed to be able to hear the whistle? Remember, you can assume the following things: The whistle you use to call your hunting dog has a frequency of 21.0 kHz, but your dog is ignoring it. You suspect the whistle may not be working, but you can't hear sounds above 20.0 kHz. The speed of sound is 330 m/s at the current air temperature.
Answer:
The minimum riding speed relative to the whistle (stationary) to be able to hear the sound at 21.0 kHz frequency is 15.7 m/s
Explanation:
The Doppler shift equation is given as follows;
[tex]f' = \dfrac{v - v_o}{v + v_s} \times f[/tex]
Where:
f' = Required observed frequency = 20.0 kHz
f = Real frequency = 21.0 kHz
v = Sound wave velocity = 330 m/s
[tex]v_o[/tex] = Observer velocity = X m/s
[tex]v_s[/tex] = Source velocity = 0 m/s (Assuming the source is stationary)
Which gives;
[tex]20 = \dfrac{330- v_o}{330+0} \times 21[/tex]
330 - [tex]v_o[/tex] = (20/21)*330
[tex]v_o[/tex] = 330 - (20/21)*330 = 15.7 m/s
The minimum riding speed relative to the whistle (stationary) to be able to hear the sound at 21.0 kHz frequency = 15.7 m/s.
Are films just a means of entertainment? Do you think films are instructional in nature? What are the functions of films? what is the role of films in a society?
Answer:
Explanation:
Films are widely popular and their audio visual nature provides them a pervasive power for social influence. Therefore, they have the potential to play an important role as a medium of entertainment, information and education and as a catalyst for social change. Films are popular because they entertain.
Movies are about sitting in a theatre, watching something- watching a story unfold with people you don't know- watching that happen and emoting an emotion knowing that for those two hours or so, when one walks into that theatre, he/she don't have to worry about what is going on outside.
A wall in a house contains a single window. The window consists of a single pane of glass whose area is 0.15 m2 and whose thickness is 7 mm. Treat the wall as a slab of the insulating material Styrofoam whose area and thickness are 17 m2 and 0.20 m, respectively. Heat is lost via conduction through the wall and the window. The temperature difference between the inside and outside is the same for the wall and the window. Of the total heat lost by the wall and the window, what is the percentage lost by the window
Answer:
88 %
Explanation:
The rate of heat loss by a conducting material of thermal conductivity K, cross-sectional area,A and thickness d with a temperature gradient ΔT is given by
P = KAΔT/d
The total heat lost by the styrofoam wall is P₁ = K₁A₁ΔT₁/d₁ where K₁ =thermal conductivity of styrofoam wall 0.033 W/m-K, A₁ = area of styrofoam wall = 17 m², ΔT₁ = temperature gradient between inside and outside of the wall and d₁ = thickness of styrofoam wall = 0.20 m
The total heat lost by the glass window is P₂ = K₂A₂ΔT₂/d₂ where K₂ =thermal conductivity of glass window pane wall 0.96 W/m-K, A₂ = area of glass window pane = 0.15 m², ΔT₂ = temperature gradient between inside and outside of the window and d₂ = thickness of glass window pane = 7 mm = 0.007 m
The total heat lost is P = P₁ + P₂ = K₁A₁ΔT₁/d₁ + K₂A₂ΔT₂/d₂
Now, since the temperatures of both inside and outside of both window and wall are the same, ΔT₁ = ΔT₂ = ΔT
So, P = K₁A₁ΔT/d₁ + K₂A₂ΔT/d₂
Since P₂ = K₂A₂ΔT₂/d₂ = K₂A₂ΔT/d₂is the heat lost by the window, the fraction of the heat lost by the window from the total heat lost is
P₂/P = K₂A₂ΔT/d₂ ÷ (K₁A₁ΔT/d₁ + K₂A₂ΔT/d₂)
= 1/(K₁A₁ΔT/d₁÷K₂A₂ΔT/d₂ + 1)
= 1/(K₁A₁d₂÷K₂A₂d₁ + 1)
= 1/[(0.033 W/m-K × 17 m² × 0.007 m ÷ 0.96 W/m-K × 0.15 m² × 0.20 m) + 1]
= 1/(0.003927/0.0288 + 1)
= 1/(0.1364 + 1)
= 1/1.1364
= 0.88.
The percentage is thus P₂/P × 100 % = 0.88 × 100 % = 88 %
The percentage of heat lost by window of the total heat is 88 %