Answer:
Explanation:
Work done on the lever ( input energy ) = force applied x input distance
= 24 N x 2m = 48 J
Work done by the lever ( output energy ) = load x output distance
= 72 N x 0.5m = 36 J
efficiency = output energy / input energy
= 36 J / 48 J
= 3 / 4 = .75
In percentage terms efficiency = 75 % .
Answer:
Net force on the block is 32 N.
Acceleration of the object is 6.4 m/s².
Explanation:
Let the acceleration of the object be
m/s².
Given:
Mass of the block is, 
Force of pull is, 
Frictional force on the block is, 
The free body diagram of the object is shown below.
From the figure, the net force in the forward direction is given as:

Now, from Newton's second law of motion, net force is equal to the product of mass and acceleration. So,

Therefore, the acceleration of the object in the forward direction is 6.4 m/s².
Period, T = 1/ f.
f = frequency = 200 Hz.
Period T = 1/200 = 0.005 seconds.
The Answer is B : The water particles become locked in place.
Answer: Work W = 0
Explanation: Work W = F·s. Because rock does not move, s = 0 and
work done is zero.