Answer:
c) It increases by a factor of 8
Explanation:
According to Faraday's law (and Lenz' law), the induced EMF is given as the rate of change of magnetic flux.
Mathematically:
V = -dФ/dt
Magnetic flux, Ф, is given as:
Ф = BA
where B = magnetic field strength and A = Area of object
Hence, induced EMF becomes:
V = -d(BA)/dt or -BA/t
If the magnetic field is increased by a factor of 4, (
) and the time required for the rod to move is decreased by a factor of 2 (
), the induced EMF becomes:
The EMF has increased by a factor of 8.
You must first convert minutes to seconds so 10*60=600
Then multiply the number of seconds by the speed so 600*2=1200 m
Answer:
The momentum of bath cars is 40000 Ns which make the difficulty to stop each car in aspect of fprce is the same.
Explanation:
Momentum (P) =mass(m) × velocity (v)
For car A,
P = m × v = 1000 × 40 = 40000 Ns
For car B,
P = m × v = 4000 × 10 = 40000 Ns
Force (F) = Momentum change(ΔΡ)/ time taken(t)
F = ΔΡ/t
When stopping the car the momentum changes from 40000 Ns to 0
So momentum change in both cars is the same. So to stop the two cars in a given time (t) you need the same force, which means you will feel same difficulty.
