Answer:
Explanation:
When saw slices wood by exerting a force on the wood , wood also exerts a reaction force on the saw in opposite direction which is equal to the force of action that is 104 N.
So torque exerted by wood on the blade
= force x perpendicular distance from the axis of rotation
= 104 x .128
=13.312 Nm.
Since this torque opposes the movement of blade , it turns the blade slower.
The work done by Joe is 0 J.
<u>Explanation</u>:
When a force is applied to an object, there will be a movement because of the applied force to a certain distance. This transfer of energy when a force is applied to an object that tends to move the object is known as work done.
The energy is transferred from one state to another and the stored energy is equal to the work done.
W = F . D
where F represents the force in newton,
D represents the distance or displacement of an object.
Force = 0 N, D = 20 cm = 0.20 m
W = 0 
0.20 = 0 J.
Hence the work done by Joe is 0 J.
Answer: F = 1391 N
Explanation:
The information given to you are:
Mass M = 1300 kg
Acceleration a = 1.07 m/s^2
The magnitude of the force striking the building will be
F = ma
Where
F = force
Substitute mass M and acceleration a into the formula
F = 1300 × 1.07
F = 1391 N
Therefore, the wrecking ball strikes the building with a force of 1391 N
Newton's 2nd law of motion:
Force = (mass) x (acceleration)
= (0.314 kg) x (164 m/s²)
= 51.5 newtons
(about 11.6 pounds) .
Notice that the ball is only accelerating while it's in contact with the racket.
The instant the ball loses contact with the racket, it stops accelerating, and
sails off in a straight line at whatever speed it had when it left the strings.
