give the relation of speed of sound with the density and temperature
Answer:
The greater the density of a medium, the slower the speed of sound. This observation is analogous to the fact that the frequency of a simple harmonic motion is inversely proportional to m, the mass of the oscillating object.
Air molecules have more energy at higher temperatures, which means they vibrate faster. This allows the sound waves to also travel faster because they are propelled by collisions between the molecules
What could be the average human density? Justify?
Answer:
985 kg/m3
Explanation:
The average density of the human body is 985 kg/m3 k g / m 3 , and the typical density of seawater is about 1020 kg/m3 k g / m 3 .
Explanation:
the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2 (38 per sq. mi.). If only the Earth's land area of 150,000,000 km2 (58,000,000 sq. mi.) is taken into account, then human population density is 50 per km2 (129 per sq.
What allows a metal to be pounded into a flat shape?
Can some one please help me
Answer:
its "up, then down, then up"
Explanation:
https://forms.office.com/Pages/ResponsePage.aspx?..
Print Management S Show My Homework
worites
10
Calculate the power in resistor X when the voltage across X is 2.1 V and the current in resistor
X is 0.041 A
(2 Points)
Answer:
P = 0.0861 W = 86.1 mW
Explanation:
The electrical power in a resistor is defined as the product of the current passing through that resistor and the voltage across that resistor. Therefore, the formula can be written as follows:
[tex]P = VI[/tex]
where,
P = Power in Resistor X = ?
V = Voltage across resistor X = 2.1 V
I = Current passing through resistor X = 0.041 A
Therefore,
[tex]P = (2.1\ V)(0.041\ A)[/tex]
P = 0.0861 W = 86.1 mW
Figure 1 shows the kinetic energy as a function of time for a 2kg object that is released from rest and falls toward Earth’s surface. Figure 2 shows the kinetic energy as a function of time for a 5kg object that is released from rest and falls toward Earth’s surface. Both objects are released simultaneously from the same height. How much does the gravitational potential energy of the object-object-Earth system change from 0s to 10s ?
a) 400J
b)600 J
c)1000 J
d) 1400J
Answer:
The answer is 1400 J, according to my Physics teacher.
Explanation:
You need to take into account everything that is listed in the question; it's important to remember that the question is asking about the change in gravitational potential energy of the object-object-Earth system from 0s to 10s, not 0s to 20s. :)
Help plz for 25 points !! I only have an hour left !
A house painter stands 3.00 m above the ground on a 5.00-m-long ladder that leans against the wall at a point 4.70 m above the ground. The painter weighs 676 N and the ladder weighs 107 N. Assuming no friction between the house and the upper end of the ladder, find the force of friction that the driveway exerts on the bottom of the ladder. If the force of friction is away from the wall, enter a negative value and if the force of friction is toward the wall, enter a positive value.
Answer:
The force of friction that the driveway exerts on the ladder ≈ -176.03 N
Please see attached force diagram created with MS Visio
Explanation:
The height of the house painter above the ground = 3.00 m
The length of the ladder = 5.00 m
The height above the ground at which the ladder leans on the wall = 4.70 m
The weight of the painter = 676 N
The weight of the ladder = 107 N
The angle of inclination of the ladder, arcsin(4.7/5) ≈ 70.05°
For equilibrium, the sum of moments at a point, ∑M = 0
Taking moment about point A gives;
4.7 × R = 107 × 2.5 × cos(arcsin(4.7/5)) + 676 × 3.0/(tan(arcsin(4.7/5)))
R = (107 × 2.5 × cos(arcsin(4.7/5)) + 676 × 3.0/(tan(arcsin(4.7/5))))/4.7 ≈ 176.03
The reaction force at the top of the ladder, R ≈ 176.03 N
For equilibrium, we have;
The sum of the horizontal forces, ∑Fₓ = 0
The reaction at the top of the ladder, R + The force of friction that the driveway exerts on the bottom of the ladder, [tex]F_R[/tex] = 0
R + [tex]F_R[/tex] = 0
∴ R = [tex]-F_R[/tex]
R ≈ 176.03 N = [tex]-F_R[/tex]
∴ [tex]F_R[/tex] = -176.03 N
Therefore, the force of friction that the driveway exerts on the bottom of the ladder, [tex]F_R[/tex] ≈ -176.03 N (acting away from the wall).
PLS HELP
According to the theory of spontaneous generation, tadpoles were believed to arise form dead flesh. True or False.
A.
FALSE
B.
TRUE
"This was the idea that non-living objects can give rise to living organisms."
A music fan at a swimming pool is listening to a radio on a diving platform. The radio is playing a constant- frequency tone when this fellow, clutching his radio, jumps off. Describe the Doppler Effect heard by (a) a person left behind on the platform and (b) a person down below floating on a rubber raft. In each case, specify (1) whether the frequency is greater or smaller than the frequency produced by the radio, (2) whether the observed frequency is constant, and (3) how the observed frequency changes during the fall, if it does change. Give your reasoning.
Answer:
The Doppler Effect is given by the following relation;
[tex]f' = \left (\dfrac{v + v_0}{v - v_s} \right) \times f[/tex]
Where;
f' = The frequency the observer hears
f = Actual frequency of the wave
v = The velocity of the sound wave
[tex]v_o[/tex] = The velocity of the observer
[tex]v_s[/tex] = The velocity of the source
Where the observer is stationary, we have;
(i) When the source is moving in the direction of the observer
[tex]f' = \left (\dfrac{v }{v - v_s} \right) \times f[/tex]
(ii) When the source is receding from the observer, we have;
[tex]f' = \left (\dfrac{v }{v + v_s} \right) \times f[/tex]
Therefore;
(a) A person left behind on the platform
For a person left behind on the platform, we have that the radio source is receding, therefore, we have;
[tex]f' = \left (\dfrac{v }{v + v_s} \right) \times f[/tex]
(1) Given that (v + [tex]v_s[/tex]) > v, therefore, v < (v + [tex]v_s[/tex]), f' < f, the frequency heard by the person left on the platform, f', is smaller (lower) than the frequency produced by the radio
(2) The frequency is not constant as the speed of the source is increasing while it under the acceleration due to gravity
(3) During the fall, the speed of the source continuously increases under the effect of gravitational attraction and therefore the frequency heard by the person on the platform becomes progressively smaller
(b) A person down below floating on a rubber raft
For the the person down below on the rubber raft, the radio source is advancing
Therefore, the radio source is moving towards the person at rest down on the rubber raft, therefore, we have;
[tex]f' = \left (\dfrac{v }{v - v_s} \right) \times f[/tex]
(1) Given that (v - [tex]v_s[/tex]) < v, therefore, f' > f, the frequency heard by the person down below floating on the rubber raft, f', is greater (higher) than the frequency produced by the radio
(2) The frequency is not constant as the speed of the source is increasing while it under the acceleration due to gravity
(3) During the fall, the speed of the source continuously increases under the effect of gravitational attraction and therefore the frequency heard by the person on the platform becomes progressively greater (higher)
Explanation:
PLZZ HELP ME PLZ I NEED YALL HELP WITH THIS LAST QUESTION
Answer:
The 5 Forces
Explanation:
The five forces that influence wind speed and direction are: Pressure gradient force (flow from high to low pressure) Coriolis force (apparent deflecting force due to the rotation of the Earth) Turbulent drag (Earth's surface or objects like trees or grass resist air flow and decrease wind speed near the ground)
When a ball is being lifted work is being done to it, giving it ______ energy.
A 1400 kg car traveling at 17.0 m/s to the south collides with a 4700 kg truck that is at rest. The car and truck stick together and move together after collision. What is the final velocity of the two-vehicle mass? If Kinetic Energy = 0.5 * m * v^2, calculate the KE before the crash and the KE of the combined vehicles after the crash.
Answer:
Final velocity = 7.677 m/s
KE before crash = 202300 J
KE after crash = 182,702.62 J
Explanation:
We are given;
m1 = 1400 kg
m2 = 4700 kg
u1 = 17 m/s
u2 = 0 m/s
Using formula for inelastic collision, we have;
m1•u1 + m2•u2 = (m1 + m2)v
Where v is final velocity after collision.
Plugging in the relevant values;
(1400 × 17) + (4700 × 0) = (1400 + 1700)v
23800 = 3100v
v = 23800/3100
v = 7.677 m/s
Kinetic energy before crash = ½ × 1400 × 17² = 202300 J
Kinetic energy after crash = ½(1400 + 1700) × 7.677² = 182,702.62 J
A light bulb has a power output of 80 W and it has been left on for 90 seconds. How much work was done?
7200 joules of heat and light energy was dissipated into the air. But no work was done ... no force moved through no distance.
HELP THIS IS TIMED PLEASE OMG
Answer:
d) 40000 kgm/s
Explanation:
The formula for momentum is p = m*v
so p = 100*400
p = 40000 kgm/s
Helppppppl!!!!!!!!!!!
Answer:
I think deposition of C is the oldest deposit
IF SOMEONE CAN'T FIND THE ANSWER I WILL COMMIT ARSON PLEASE HELP MEE
Brainliest + random amount of points please help me It's a crossword
Answer:
Freefall
Explanation:
Hi the answer is freefall, hope this helps :)
what is the difference between storm spotter and storm chaser?
Answer:
this is just a guess
Explanation:
a storm spotter only spots the storm and a storm chaser looks for the storm????
An electric toy with a resistance of 2.50\,\Omega is operated by a 3.00\,\text{V} battery. (c) How much energy was delivered to the toy [over four hours]?
Answer:
Energy = 51840 J = 51.84 KJ
Explanation:
The electrical energy delivered to the toy can be found out by the following formula:
[tex]Energy = (Power)(time)\\Energy = (VI)(t)\\Enegry = VIt\\[/tex]
where,
V = Voltage = 3 V
R = Resistance = 2.5 Ω
I = Current = V/R (Ohm's Law) = 3 V/2.5 Ω = 1.2 A
t = time = (4 h)(3600 s/1 h) = 14400 s
Therefore,
[tex]Energy = (3\ V)(1.2\ A)(14400\ s)\\[/tex]
Energy = 51840 J = 51.84 KJ
eeeee
help pls
pls
pls
Answer:
hey dream I m your big fan for u I have answered this question The third one is correct.
a car travels for two hours at an average speed of 36 km/h how far will the car travel
Answer:
259200
Explanation:
use the formula distance= speed x time
change the 2 hours to seconds (7200) and multiply that number by 36 and it'll give you 259200
Answer:
12 kilometers and hour
Explanation:
how does the input distance of a third-class lever compare to the output distance
Answer:
A first-class lever: fulcrum is between input and output force; second-class lever: output force is between input force and fulcrum; third-class lever: input force is between fulcrum and output force
Electricity is the _____________ of electrons, because electrons _____________ from atom to atom.
Electricity is the [tex]\sf{\underline{flow}}[/tex] of electrons, because electrons [tex]\sf{\underline{passes}}[/tex] from atom to atom.
please help its worth 10 points
no links please!
Answer:
which question
Someone please help me with this !??
3. What does the difference in force depend on?
Answer:
it depends on the relative masses of the objects.
Explanation:
When the number of gas particles at a constant pressure decreases how will the volume of the gas change?
Compare the kinetic and potential energies of a 400 kg box being moved
horizontally by a forklift at a speed of 5 m/s. The box is at a height of 1 m.
A. PE = 400 J; KE = 1,000 J
B. PE = 3,920 J; KE = 5,000 J
C. PE = 3,920 J; KE = 1,000 J
D. PE = 5,000 J; KE = 3,920 J
Answer: B is the answer .
Explanation:
The weight of a cuboid box is 288 N. Find its mass.
Answer:
29.39 kg
Explanation:
From the question,
W = mg...................... Equation 1
Where W = weight of the cuboid box, m = mass of the cuboid box, g = acceleration due to gravity.
make m the subject of the equation
m = W/g.................. Equation 2
Given: W = 288 N
Constant: g = 9.8 m/s²
Substitute these values into equation 2
m = 288/9.8
m = 29.39 kg
Would the following reaction be endothermic or exothermic? Why?
CH4 + 02 --> CO2 + H2O + Energy
A. Exothermic because energy is a reactant
B. Endothermic because energy is a reactant
C. Endothermic because energy is a product
D. Exothermic because energy is a product
Answer:
D. Exothermic because energy is a product
Explanation:
ENDOTHERMIC REACTION: A chemical reaction is considered endothermic if the energy is absorbed during the reaction. In other words, if the energy is required by the reactants to proceed with the reaction, then the reaction is endothermic.
EXOTHERMIC REACTION: A chemical reaction is considered exothermic if the energy is released during the reaction. In other words, if the energy is produced as a product of the reaction, then the reaction is exothermic.
Hence, the correct answer for this question will be:
D. Exothermic because energy is a product