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2 years ago

Jenny pushes a 40 N crate down the hall 2m. How much work did she do?

Physics

1 answer:

Shalnov [3]2 years ago

8 0

Work done = force x distance = 40 x 2 = 80 Joules.

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The Sun appears to move across the sky during the day. The best explanation for this apparent motion is that Earth is

Harrizon [31]

Answer:

Explanation:

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2 years ago

Read 2 more answers

A jogger accelerates from rest to 4.86 m/s in 2.43 s. A car accelerates from 20.6 to 32.7 m/s also in 2.43 s. (a) Find the magni

Aleonysh [2.5K]

Explanation:

It is given that,

Initially, the jogger is at rest u₁ = 0

He accelerates from rest to 4.86 m, v₁ = 4.86 m

Time, t₁ = 2.43 s

A car accelerates from u₂ = 20.6 to v₂ = 32.7 m/s in t₂ = 2.43 s

(a) Acceleration of the jogger :

$a=\dfrac{v-u}{t}$

$a=\dfrac{4.86\ m/s-0}{2.43\ s}$

a₁ = 2 m/s²

(b) Acceleration of the car,

$a=\dfrac{v-u}{t}$

$a=\dfrac{32.7\ m/s-20.6\ m/s}{2.43\ s}$

a₂ = 4.97 m/s²

(c) Distance covered by the car,

$d_1=u_1t_1+\dfrac{1}{2}a_1t_1^2$

$d_1=0+\dfrac{1}{2}\times 2\times (2.43)^2$

d₁ = 5.904 m

Distance covered by the jogger,

$d_2=u_2t_2+\dfrac{1}{2}a_2t_2^2$

$d_2=20.6\times 2.43+\dfrac{1}{2}\times 4.97\times (2.43)^2$

d₂ = 64.73 m

The car further travel a distance of, d = 64.73 m - 5.904 m = 58.826 m

Hence, this is the required solution.

5 0

2 years ago

The bolts on a car wheel require tightening to a torque of 4 N*m. If a 9 cm long wrench is used, what is the magnitude of the fo

notsponge [240]

Answer:

320N

Explanation:

The magnitude of the torque required is expressed using the formula;

T = Fr sin theta where;

F is the force

r is the radius = 9cm = 0.09m

theta is the angle of inclination = 8 degrees

Torque T = 4Nm

Substitute the given values and get F

4 = F(0.09)sin8

4 = 0.0125F

F = 4/0.0125

F = 320N

Hence the magnitude of the force required when the force is applied at 8 degrees to the wrench is 320N

7 0

2 years ago

A mass M of 3.80E-1 kg slides inside a hoop of radius R=1.10 m with negligible friction. When M is at the top, it has a speed of

Vikentia [17]

Answer:

N = 26.59 N

Explanation:

given,

mass = 0.38 kg

radius of the hoop = 1.10 m

speed = 5.35 m/s

force = ?

now,

$\dfrac{1}{2}mv_t^2 + mg(2R) = \dfrac{1}{2}mv^2 + mgR(1-cos \theta)$

$mv^2 = mv_t^2 + 2mgR(1 + cos \theta)$

we know that,

$N - mgcos \theta = \dfrac{mv^2}{R}$

$N - mgcos \theta = \dfrac{mv_t^2 + 2mgR(1 + cos \theta)}{R}$

$N - mgcos \theta = \dfrac{mv_t^2 }{R}+ 2mg(1 + cos \theta)$

$N = \dfrac{mv_t^2 }{R}+ 2mg + 3mgcos \theta)$

$N = \dfrac{0.38\times 5.35^2 }{1.1}+ 2\times 0.38\times 9.8 + 3\times 0.38 \times 9.8 cos 34^0)$

N = 26.59 N

3 0

2 years ago

PLEASE HELP!!!!!!!!! 30 POINTS

ivolga24 [154]

Answer: experiment data is the things you do in the experiment and the result is the answer

4 0

2 years ago