Answer:
Speed of gamma rays = 3 x 10⁸ m/s
Explanation:
Given:
Frequency of gamma ray = 3 x 10¹⁹ Hz
Wavelength of gamma rays = 1 x 10⁻¹¹ meter
Find:
Speed of gamma rays
Computation:
Velocity = Frequency x wavelength
Speed of gamma rays = Frequency of gamma ray x Wavelength of gamma rays
Speed of gamma rays = [3 x 10¹⁹][1 x 10⁻¹¹]
Speed of gamma rays = 3 x [10¹⁹⁻¹¹]
Speed of gamma rays = 3 x [10⁸]
Speed of gamma rays = 3 x 10⁸ m/s
Answer:
Apply Newton's second law in the moving direction.
Explanation:

Friction force applies in the opposite direction of motion; as a restriction.
Answer:
A) 
B) 
C) 
Explanation:
Given:
- mass of flywheel,

- diameter of flywheel,

- rotational speed of flywheel,

- duration for which the power is off,

- no. of revolutions made during the power is off,

<u>Using equation of motion:</u>



Negative sign denotes deceleration.
A)
Now using the equation:


is the angular velocity of the flywheel when the power comes back.
B)
Here:

Now using the equation:


is the time after which the flywheel stops.
C)
Using the equation of motion:


revolutions are made before stopping.
Answer:
Explanation:
Given that,
Number of turn N = 40
Diameter of the coil d= 11cm = 0.11m
Then, radius = d/2 = 0.11/2 =0.055m
r = 0.055m
Then, the area is given as
A =πr²
A = π × 0.055²
A = 9.503 × 10^-3 m²
Magnetic Field B = 0.35T
Magnetic field reduce to zero in 0.1s, t = 0.1s
so we want to find induce electric field. To find the electric field,(E) we need to find the electric potential (V).
E.M.F is given as
ε = —N • dΦ/dt
Where magnetic flux is given as
Φ = BA
Then, ε = —N • dΦ/dt
ε = —N • dBA/dt
ε = —NBA/t
Then, its magnitude is
ε = NBA/t
Inserting the values of N, B, A and t
ε = 40×0.35×9.503×10^-3/0.1
ε = 1.33 V
Then, using the relationship between Electric field and electric potential
V = Ed
ε = E•d
E = ε/d
E = 1.33/0.11
E = 12.09 V/m