Answer:
Explanation:
magnetic filed, B = 0.65 T
initial diameter, d = 17.5 cm
final diameter, d' = 6.6 cm
time, t = 0.48 s
(a) According to Lenz's law, the direction of induced current is clockwise.
(b) Let e is the induced emf.
initial area, A = π r² = 3.14 x 0.0875 x 0.0875 = 0.024 m²
final area, A' = π r'² = 3.14 x 0.033 x 0.033 = 0.00342 m²
change in area, ΔA = A - A' = 0.024 - 0.00342 = 0.02058 m²
The magnitude of induced emf is given by


e = 0.65 x 0.02058 / 0.48
e = 0.028 V
(c) R = 2.5 ohm
i = e / R
i = 0.028 / 2.5
i = 0.011 A
B. Gravity and air resistance.
Answer:
The value of new value of angular speed of merry go round.
= 0.96 
Explanation:
Given data
r = 1.4 m
Moment of inertia
= 265 kg - 
11 RPM


= 1.15 
From conservation of momentum principal
------- (1)



Put all the values in equation (1)
265 × 1.15 = 317.92 × 
= 0.96 
This is the value of new value of angular speed of merry go round.
Answer:
The light bulb would glow brighter.
Explanation:
Resistance is the opposition to current flow and in Ohm's law is represented as a constant in the equation V = IR with V the voltage, I the current and R the resistance.
Now let's assume we are in a series circuit that has only one path for electricity to follow to better explain what would happen to a light bulb if the voltage increased but the resistance stayed the same. Based on ohm's law equation, the voltage is directly proportional to the current and the resistance is constant. An increase in the voltage is therefore an increase in the current which flows throught the light bulb making it glow brighter while a decrease in voltage results in a decrease in current flowing through the light bulb making it dim.
Here in all such collision type question we can use momentum conservation as we can see that there is no external force on this system

as we know that




now from above equation we have



so the speed of combined system is 2 m/s