Material composing the body,
temperature of the body and the length of the body affects the electrical
resistance of a body. Bodies directly surrounding the body will not affect the
electrical resistance of the body. The answer is letter D.
Answer:


The motion of the block is downwards with acceleration 1.7 m/s^2.
Explanation:
First, we will calculate the acceleration using the kinematics equations. We will denote the direction along the incline as x-direction.

Newton’s Second Law can be used to find the net force applied on the block in the -x-direction.

Now, let’s investigate the free-body diagram of the block.
Along the x-direction, there are two forces: The x-component of the block’s weight and the kinetic friction force. Therefore,

As for the static friction, we will consider the angle 31.8, but just before the block starts the move.

What a fan does is create a wind chill effect. ... By blowing air around, the fan makes it easier for the air to evaporate sweat from your skin, which is how you eliminate body heat. The more evaporation, the cooler you feel.
Answer:
vi) Double the current in the wire, and double the number of turns in the 20-cm long solenoid
Explanation:
The magnetic field inside the solenoid and the current flowing in the coil of solenoid are related to each other by the following equation
B₀=μ₀nI₀
Where,
B₀ is the magnetic field in the middle of solenoid
n is the number of turns in the coil of solenoid
I₀ is the current flowing in the coil of solenoid
In the above equation, as μ₀ is a constant so the magnetic field will be directly proportional to the number of turns multiplied by the current. So, changing the radius of the coil or length of the coil will have no effect on the magnetic field.
As we have to increase the magnetic field by 4 times, we need to double the current as well as the number of turns as mentioned in the option vi.
B. A hypothesis is just an idea. And can become a Theory if there is some evidence. However a Theory is not a law, but an idea with supportive evidence