Answer:
here the coil must be oriented in such a way that its plane is perpendicular to the magnetic field
Explanation:
As we know by Faraday's law of electromagnetic induction
Rate of change in magnetic flux will induce EMF in the coil
so here we will have

here we know that

now if the magnetic flux will change with time then it will induce EMF in the coil

so here induced EMF will be zero in the coil if the flux linked with the coil will remain constant
so here the coil must be oriented in such a way that its plane is perpendicular to the magnetic field
In such a way when coil will rotate then the flux linked with the coil will remains constant and there will be no induced EMF in it
Answer:

Explanation:
We can try writing the equation of the horizontal component of the length of the minute hand in terms of distance and the angle, that depends of time in this particular case.
The x-component of the length of the minute hand is:
(1)
- d is the length of the minute hand (d=D/2)
- D is the diameter of the clock
- t is the time (min)
Now, using the angular kinematic equations we can express the angle in term of angular velocity and time. As we know, the minute hand moves with a constant angular velocity, so we can use this equation:
(2)
Also we know, that the minute hand moves 90 degrees or π/2 rad in 15 min, so using the definition of angular velocity, we have:
Now, let's put this value on (2)
Finally the length x(t) of the shadow of the minute hand as a function of time t, will be:

I hope it helps you!
Answer:(a)891.64 N
(b)0.7
Explanation:
Mass of crate 
Crate slows down in 
initial speed 
inclination 
From Work-Energy Principle
Work done by all the Forces is equal to change in Kinetic Energy




change in kinetic energy

(b)Coefficient of sliding friction



and 


When the body touches the ground two types of Forces will be generated. The Force product of the weight and the Normal Force. This is basically explained in Newton's third law in which we have that for every action there must also be a reaction. If the Force of the weight is pointing towards the earth, the reaction Force of the block will be opposite, that is, upwards and will be equivalent to its weight:
F = mg
Where,
m = mass
g = Gravitational acceleration
F = 5*9.8
F = 49N
Therefore the correct answer is E.