Answer:
Part a)

Part b)

Explanation:
Since the ball and rod is an isolated system and there is no external force on it so by momentum conservation we will have

here we also use angular momentum conservation
so we have

also we know that the collision is elastic collision so we have

so we have

also we know

also we know

so we have


now we have


Part b)
Now we know that speed of the ball after collision is given as

so it is given as

Answer:
d. It is equal to the component of the gravitational force acting down the ramp.
Explanation:
The stationary crate is inclined at an angle with the horizontal. The Recall, Frictional Force is any Force that opposes motion.
Because the Force of Friction that is opposing the motion of the crate along the inclination side.
Therefore this Frictional force is balanced or equal to the force that is driving the inclined force.
Hence Frictional Force is equal to the Gravitational Force that is acting in the ramp, that is why the crate is stationery.
Explanation:
A chemical reaction in which heat or energy is released is known as an exothermic reaction.
On the other hand, when two objects are placed together and heat flows from hotter object to colder object then this process is known as conduction. Therefore, energy is dissipated in conduction process.
Since energy released released goes into the atmosphere and is not used anywhere.
Thus, we can conclude that when an exothermic reaction releases thermal energy, this energy is usually not useable to do work and it is dissipated by conduction.
Answer:
b
Explanation:
n = m(g +a)
n= normal force (N)
m=mass (kg)
g=acceleration of gravity
a= acceleration of elevator
rearrange:
a= n/m - g
a= (810 N/73 kg) - 9.8 m/s ^2
a= 1.3 m/s ^2 up
and the acceleration is upwards bc her weight is less than the scale reading