All categories

4 years ago

A boy performs 100 J of work pushing a chair a distance of 4 m. How much

Physics

1 answer:

olga55 [171]4 years ago

6 0

Answer:

25 N

Explanation:

Force can be found using the following formula.

F=w/d

where w is the work and d is the distance. We know that 100 Joules of work pushes the chair 4 meters. Therefore,

w=100 J

d= 4 m

F=100 J/ 4 m

Divide 100 by 4

100/4=25

F= 25 J/m

1 joule per meter, or J/m is equal to 1 Newton, or N.

F=25 N

The boy uses 25 Newtons of force.

You might be interested in

A 17926-lb truck enters an emergency exit ramp at a speed of 75.6 ft/s. It travels for 6.4 s before its speed is reduced to 30.3

I am Lyosha [343]

Answer:

$F_{braking}=337299 pdl$

Explanation:

Impulse-Momentum relation:

$I=\Delta p\\ F_{total}*t=m(v_{f}-v{o})$

$F_{total}=-F_{braking}+mgsin{\theta}$

We solve the equations in order to find the braking force:

$F_{braking}=m(v_{o}-v{f})/t+mgsin{\theta}=17926(75.6-30.3)/6.4+17926*32.17*sin21.4=337299 pdl$

6 0

3 years ago

59. (II) The crate shown in Fig. 4-60 lies on a plane tilted at an angle A = 25.0° to the horizontal, with Mk 0.19. (a) Determin

Daniel [21]

Explanation:

a) We need to write down first Newton's 2nd law as applied to the given system. The equations of motion for the x- and y-axes can be written as follows:

$x:\;\;\;\;\;mg\sin 25° - \mu_kN = ma\;\;\;\;\;\;(1)$

$y:\;\;\;\;\;N - mg\cos 25° = 0\;\;\;\;\;\;\;\;\;(2)$

From Eqn(2), we see that

$N = mg\cos 25°\;\;\;\;\;\;\;(3)$

so using Eqn(3) on Eqn(1), we get

$mg\sin 25° - \mu_kmg\cos 25° = ma$

Solving for the acceleration, we see that

$a = g(\sin 25° - \mu_k\cos 25°)$

$\;\;\;\;= 2.45\:\text{m/s}^2$

b) Now that we have the acceleration, we can now solve for the velocity of the crate at the bottom of the plane. Using the equation

$v^2 = v_0^2 + 2ax$

Since the crate started from rest, $v_0 = 0.$ Thus our equation reduces to

$v^2 = 2ax \Rightarrow v = \sqrt{2ax}$

$v = \sqrt{2(2.45\:\text{m/s}^2)(8.15\:\text{m})}$

$\;\;\;\;= 6.32\:\text{m/s}$

6 0

3 years ago

Renewable resources need to be conserved because

creativ13 [48]

Answer:

(A) We are using them faster than they are replenished by nature

4 0

3 years ago

Which of the following is WRONG?

iren2701 [21]

It’s D the time period within pendulums are constant, distance is always measured with kilometers within cities and basic unit is always seconds.

3 0

3 years ago

Read 2 more answers

A boy carries a 50 N box up a flight of stairs 10-m high. How much potential energy has the box gained?

almond37 [142]

Answer:

Potential energy, P = 500 J

Explanation:

We have,

Weight of the box, W = 50 N

Height of the stairs, h = 10 m

It is required to find the potential energy gained by the box. The potential energy is possessed by an object due to its height. The formula of potential energy is given by :

$P=mgh$

g is acceleration due to gravity

$P=50\ N\times 10\ m\\\\P=500\ J$

So, the potential energy of 500 J is gained by the box.

3 0

3 years ago