Answer:

Explanation:
Mass of a hockey puck, m = 0.17 kg
Force exerted by the hockey puck, F' = 35 N
The force of friction, f = 2.7 N
We need to find the acceleration of the hockey puck.
Net force, F=F'-f
F=35-2.7
F=32.3 N
Now, using second law of motion,
F = ma
a is the acceleration of the hockey puck

So, the acceleration of the hockey puck is
.
Answer:
The skater's speed after she stops pushing on the wall is 1.745 m/s.
Explanation:
Given that,
The average force exerted on the wall by an ice skater, F = 120 N
Time, t = 0.8 seconds
Mass of the skater, m = 55 kg
It is mentioned that the initial sped of the skater is 0 as it was at rest. The change in momentum of skater is :

The change in momentum is equal to the impulse delivered. So,

So, the skater's speed after she stops pushing on the wall is 1.745 m/s.
1) weight of the box: 980 N
The weight of the box is given by:

where m=100.0 kg is the mass of the box, and
is the acceleration due to gravity. Substituting in the formula, we find

2) Normal force: 630 N
The magnitude of the normal force is equal to the component of the weight which is perpendicular to the ramp, which is given by

where W is the weight of the box, calculated in the previous step, and
is the angle of the ramp. Substituting, we find

3) Acceleration: 
The acceleration of the box along the ramp is equal to the component of the acceleration of gravity parallel to the ramp, which is given by

Substituting, we find

Answer: TRUST ME I GOT IT WRONG the answer is B
Explanation:
Answer:
Explanation:
Let electric potential at A ,B and C be Va , Vb and Vc respectively.
Work done = charge x potential difference
Wab = q ( Va - Vb )
Wac = q ( Va - Vc )
Given
Wac = - Wab / 3
3Wac = - Wab
Now
Wbc = q ( Vb - Vc )
= q [ ( Va-Vc ) - ( Va - Vb )]
= Wac - Wab
= Wac + 3Wac
= 4Wac