A skateboarder travels on a horizontal surface with an initial velocity of 4.2 m/s toward the south and a constant acceleration of 2.6 m/s^2 toward the east. Let the x direction be eastward and the y direction be northward, and let the skateboarder be at the origin at t=0.

Required:
a. What is her x position at t=0.60s?
b. What is her y position at t=0.60s?
c. What is her x velocity component at t=0.60s?
d. What is her y velocity component at t=0.60s?

Answer:

0.705 m/s²

Explanation:

a) The sprinter accelerates uniformly from rest and reaches a top speed of 35 km/h at the 67-m mark.

Using newton's law of motion:

v² = u² + 2as

v = final velocity = 35 km/h = 9.72 m/s, u = initial velocity = 0 km/h,  s = distance = 67 m

9.72² = 0² + 2a(67)

134a = 94.484

a = 0.705 m/s²

b) The sprinter maintains this speed of 35 km/h for the next 88 meters. Therefore:

v = 35 km/h = 9.72 m/s, u = 35 km/h = 9.72 m/s, s = 88 m

v² = u² + 2as

9.72² = 9.72² + 2a(88)

176a = 9.72² - 9.72²

a = 0

c) During the last distance, the speed slows down from 35 km/h to 32 km/h.

u = 35 km/h = 9.72 m/s, v = 32 km/h = 8.89 m/s, s = 200 - (67 + 88) = 45 m

v² = u² + 2as

8.89² = 9.72² + 2a(45)

90a = 8.89² - 9.72²

90a = -15.4463

a = -0.1716 m/s²

The maximum acceleration is 0.705 m/s² which is from 0 to 67 m mark.

Answer:

ω = 0.571 rad/s

Explanation:

given data

radius = 30 m

solution

we take here g = 9.8 m/s²

and g is express as

g = r × ω²     ....................1

put here value and we get

9.8 = 30 × ω²

solve it we get

ω = 0.571 rad/s

Answer: a. m = 7.7 kg

              b. V = 435.52 in³

              c. m = 1927 kg

              d. V = 335.37 cm³

              e. m = 3 kg

Explanation: Density is the ratio of mass per volume, i.e., it's the measure of an object's compactness. Its representation is the greek letter ρ.

The formula for density is

[tex]\rho=\frac{m}{V}[/tex]

Density's unit in SI is kg/m³, but it can assume lots of other units.

Some unit transformations necessary for the resolution of the question:

1 L = 1 dm³ = 1000 cm³

1 in³ = 16.3871 cm³

1 g = 0.001 kg

a. V = 1.34 L = 1340 cm³

[tex]\rho=\frac{m}{V}[/tex]

[tex]m=\rho.V[/tex]

m = 5.75 * 1340

m = 7705 g => 7.705 kg

Mass of object 1 with volume 1.34L is 7.7 kg.

b. A cube's volume is calculated as V = side³

V = 7.58³

V = 435.52 in³

Volume of object 2 is 435.52 in³.

c. Using 1 in³ = 16.3871 cm³ to change units:

V = 435.52 * 16.3871

V = 713689.4 cm³

Then, mass will be

[tex]m=\rho.V[/tex]

m = 2.7 * 713689.4

m = 1926961.4 g => 1927 kg

Mass of object 2 is 1927 kg.

d. Volume of a sphere is calculated as [tex]V=\frac{4}{3}.\pi.r^{3}[/tex]

Diameter is twice the radius, then r = 4.31 cm.

Volume is

[tex]V=\frac{4}{3}.\pi.(4.31)^{3}[/tex]

V = 335.37 cm³

Volume of object 3 is 335.37 cm³.

e. [tex]m=\rho.V[/tex]

m = 8.96 * 335.37

m = 3004.91 g => 3 kg

Mass of object 3 is 3 kg.

Answer:

C

Explanation:

Hope this helps!!!!

Answer:

i Believe the correct answer is "An open circuit being changed into a closed circuit"

Explanation:

in the service producing sector

Answer:

the number density of the protons in the beam is 3.2 × 10¹³ m⁻³

Explanation:

Given that;

diameter D = 2.0 mm

current I = 1.0 mA

K.E of each proton is 20 MeV

the number density of the protons in the beam = ?

Now, we make use of the relation between current and drift velocity

I = MeAv ⇒ 1 / eAv

The kinetic energy of protons is given by;

K = [tex]\frac{1}{2}[/tex][tex]m_{p}[/tex]v²

v = √( 2K / [tex]m_{p}[/tex] )

lets relate the cross-sectional area A of the beam to its diameter D;

A = [tex]\frac{1}{4}[/tex]πD²

now, we substitute for v and A

n = I / [tex]\frac{1}{4}[/tex]πeD² ×√( 2K / [tex]m_{p}[/tex] )

n = 4I/π eD² × √([tex]m_{p}[/tex] / 2K )

so we plug in our values;

n = ((4×1.0 mA)/(π(1.602×10⁻¹⁹C)(2mm)²) × √(1.673×10⁻²⁷kg / 2×( 20 MeV)(1.602×10⁻¹⁹ J/ev )

n =  1.98695 × 10¹⁸ × 1.6157967  × 10⁻⁵

n = 3.2 × 10¹³ m⁻³  

Therefore, the number density of the protons in the beam is 3.2 × 10¹³ m⁻³

Answer:

- the Thevenin equivalent circuit for the battery is uploaded below

- the battery delivered 117 watts of power to the starter motor

Explanation:

Given the data in the equation

diagram of the Thevenin equivalent circuit for the battery is uploaded below.

Current I = 10 A

Voltage 1 = 12 V

voltage 2 = 11.7 v

R = (V1 - V2) / I

R = (12-11.7)/10

R = 0.3 / 10

R = 0.03Ω

Thevenin equivalent circuit

[tex]R_{L}[/tex] = V2 / I = 11.7 / 10

[tex]R_{L}[/tex] = 1.17Ω

so, power delivered to the starter motor will be;

p = (V2)² / [tex]R_{L}[/tex]

P = ( 11.7 V )² / 1.17Ω

p =  136.89 / 1.17

p =  117 watts

Therefore, the battery delivered 117 watts of power to the starter motor

Answer:

Explanation:

The box is moving with constant velocity so acceleration of box is zero . That means net force on the box is zero .

The weight component acting on box parallel to incline plane

= mg sin 30⁰ = 20 x 9.8 x sin 30 = 98 N

This force is acting down the plane , hence to make the net force zero acting on box , force exerted by person will also be 98 N up the incline .

Force exerted by person = 98 N

distance travelled in 5 s

= velocity x time

= 2 x 5 = 10 m

Work done by person

= 98 x 10

= 980 J .

Answer:

4.8mph

Explanation:

Speed= Distance/time

Speed= 26.2/5.5

= 4.76mph

( To the nearest tenth ) = 4.8mph

Answer:

38.7 mph

Explanation:

I just add all the numbers together then divided them by 4, which is the amount of numbers you gave.

Answer:

g₂ = 39 m / s²

Explanation:

Mass is the amount of matter that a body has, so it does not change, but the weight is the force with which the planet attracts this matter, this value does change

           W = m g

let's use subscript 1 for the first planet and subscript 2 for the second planet

           W₁ = m₁ g₁

           W₂ = m₂ g₂

They give us the values ​​of the masses and the value of g₁ = 7.0 m / s, let's find the value of the acceleration of gravity on Planet 2

They tell us that the weight of the two astronauts is the same therefore

          W₁ = W₂ = W

let's match the expressions

             m₁ g₁ =m₂ g₂

             g₂ = [tex]\frac{m_1}{m_2} \ g_1[/tex]

let's calculate

              g₂ = [tex]\frac{70}{80} \ 7.0[/tex]      

              g₂ = 39.2 m / s²

              g₂ = 39 m / s²

Answer:

F = 228.24 N

Explanation:

       where pf = final momentum = m*vf

                  p₀ = initial momentum = m*v₀

       [tex]m*v_{f} - m*v_{o} = -2*v_{o} -m*v_{o} = -3*m*v_{o} = -3*0.3kg*12.68m/s = -11.41m/s (2)[/tex]

       [tex]F_{net} = \frac{-11.41m/s}{0.05s} = -228.24 N (3)[/tex]

Answer:

C the metal handle because it is a good conductor

Answer:

D.

Explanation:

Although the metal handle will last longer, if heated up enough it could burn her hand.

Answer:

I think A

Explanation:

because I don't think a unknowned number can be a division problem

Answer:

some kind of chemical of which i do not know

Explanation:

Answer:

c heats up cancer cells and weakens them.

Answer:

I think it is C

Explanation:

because

Answer:

(A)  the acceleration  experienced by the proton 2.821 x 10¹² m/s²

(B) the speed of the proton is 2.67 x 10⁵ m/s

Explanation:

Given;

electric field experienced by the proton, E = 2.95 x 10⁴ N/C

charge of proton, Q = 1.6 x 10⁻¹⁹ C

mass of proton, m = 1.673 x 10⁻²⁷ kg

distance moved by the proton, d = 1.26 cm = 0.0126 m

(a)

The force experienced by the proton is calculated as;

F = ma = EQ

where;

a is the acceleration  experienced by the proton

[tex]a = \frac{EQ}{m} \\\\a = \frac{2.95\times 10^4 \ \times \ 1.6\times 10^{-19}}{1.673 \times 10^{-27}} \\\\a = 2.821 \times 10^{12} \ m/s^2[/tex]

(b) the speed of the proton is calculated;

v² = u² + 2ad

v² = 0 + (2 x 2.821 x 10¹² x 0.0126)

v² = 7.109 x 10¹⁰

v = √7.109 x 10¹⁰

v = 2.67 x 10⁵ m/s

Answer:

V = 20m/s

Explanation:

Given the following data;

Acceleration = 4m/s²

Time = 10 secs

Initial velocity = 0m/s (since it's at rest).

To find the average velocity, we would use the first equation of motion;

[tex] V = U + at[/tex]

Where;

V is the final velocity.

U is the initial velocity.

a is the acceleration.

t is the time measured in seconds.

Substituting into the equation, we have;

V = 0 + 4*10

V = 40m/s

To find the average velocity;

Average velocity = (U + V)/2

Average velocity = (0 + 40)/2

Average velocity = 40/2

Average velocity = 20m/s

Answer: an ant eater who can’t eat

Explanation:

Answer:

Explanation:

For resistance , the expression is as follows .

R = ρ L / S where ρ is specific resistance , L is length of wire and S is cross sectional area .

cross sectional area = π x ( .5 x 10⁻³ )²

S = .785 x 10⁻⁶ m²

Putting the values

R = 2.82 x 10⁻⁸ x .50 / .785 x 10⁻⁶

= 1.796 x 10⁻² ohm .

Answer: I don't know my dude

Explanation:

Answer:

See explanation below

Explanation:

This is a typical exercise of free falling. In this case a rock thrown straight down from the bridge, and we are asked to determine the final velocity of the rock and it's displacement at those given times.

First, just for this problem, as the rock is going straight down, we'll say that the downward direction is positive, therefore, the following expressions to calculate velocity and speed will be:

V = V₀ + gt   (1)

X = V₀t + gt²/2   (2)

In this case, g = 9.8 m/s²

Now, let's see the displacement and velocity for each given time:

a) For  t = 0.5 s

V = 14 + (9.8)*0.5

V = 18.9 m/s

X = (14*0.5) + (9.8)(0.5)²/2

X = 7 + 1.225

X = 8.225 m

b) For t = 1.00 s

V = 14 + (9.8)*1

V = 23.8 m/s

X = (14*1) + (9.8)(1)²/2

X = 14 + 4.9

X = 18.9 m

c) For t = 1.5 s

V = 14 + (9.8)*1.5

V = 28.7 m/s

X = (14*1.5) + (9.8)(1.5)²/2

X = 21 + 11.025

X = 32.025 m

d) For t = 2 s

V = 14 + (9.8)*2

V = 33.6 m/s

X = (14*2) + (9.8)(2)²/2

X = 28 + 19.6

X = 47.6 m

e) For t = 2.50 s

V = 14 + (9.8)*2.5

V = 38.5 m/s

X = (14*2.5) + (9.8)(2.5)²/2

X = 35 + 30.625

X = 65.625 m

Hope this helps

Answer:

a

Explanation:

i just took the test

Answer:

The answer is below

Explanation:

Let a be the initial velocity of motorcycle A and b be the initial velocity of motorcycle B.

After 5.68 seconds, both motorcycle had the same velocity (v), therefore for motorcycle A:

(a - v) / 5.68 = 3.87

a - v = 21.9816

v = a - 21.9816

For motorcycle B:

(b - v) / 5.68 = 18.2

b - v = 103.376

v = b - 103.376

Therefore:

a - 21.9816 = b - 103.376

b - a = -21.9816 + 103.376

b - a = 81.3944

a) The difference between their speeds at the beginning was 81.3944 m/s

b) Since b - a = 81.3944. This means that the initial velocity of motorcycle B is greater than that of motorcycle A by 81.3944 m/s.

Therefore motorcycle B was moving faster

HERE IS YOUR ANSWER!