Answer:
0.025 A
Explanation:
A = 50 cm^2 = 50 x 10^-4 m^2
B2 = 6 T, B1 = 2 T
db = 6 - 2 = 4 T
dt = 2 s
R = 0.4 ohm
Let i be the magnitude of induced current and e be the induced emf.
According to the Faraday's law of electromagnetic induction
e = dФ / dt
e = A dB / dt
e = 50 x 10^-4 x 4 / 2 = 0.01 V
i = e / R = 0.01 / 0.4 = 0.025 A
They measured the wavelength of light emitted by stars using spectrometers and found it was being redshifted.
This implied the stars were moving away aka the space between the scientists and the star was expanding
work done is product of force and displacement of point of application of force
so here we have to check the product of force and displacement both
Now we will put the least to maximum work in the following order
1. -A man exerts strenuous effort in pushing a stationary wall
2. -A flea pushes a speck of dirt 1 cm
3. -A farmer pushes a 2 kg wheelbarrow 20 m
4. -A cannon launches a 3 kg cannonball a distance of 200
5. -A 2000 kg car travels 400 m down a road
6. -Space shuttle Atlantis launches from the ground into near-Earth orbit
Answer:
An electric motor is a device that changes electrical energy into mechanical energy. This change occurs due to the interaction between the magnetic field of magnets and the magnetic field due to the electric current in the loop. The interaction between the two produces a torque that makes the loop rotate on a shaft.