Answer:
a) 
b) 
Explanation:
The law of conservation of mechanical energy states that total mechanical energy remains constant during oscillation. Mechanical energy is defined as the sum of kinetic energy and potential energy:

a) The position is one-third the amplitude. So, we have
. Replacing and solving for K

b) The potential energy is defined as:

Replacing:

Answer:

Explanation:
We are given that a parallel- plate capacitor is charged to a potential difference V and then disconnected from the voltage source.
1 m =100 cm
Surface area =S=


We have to find the charge Q on the positive plates of the capacitor.
V=Initial voltage between plates
d=Initial distance between plates
Initial Capacitance of capacitor

Capacitance of capacitor after moving plates


Potential difference between plates after moving








Hence, the charge on positive plate of capacitor=
Answer:

Explanation:
Given that,
Initial angular velocity, 
Final angular speed, 
Angular displacement, 
We need to find the angular acceleration of the tire. We can find it using the third equation of rotational kinematics. So,

So, the angular acceleration of the tire is equal to
.
Answer:
8387 J
Explanation:
work produced= 5284 J
efficiency of 63%
the efficiency η= Work done÷ heat supplied


solving 
therefore, the input heat= 8387 J