Answer
2) 1.5×10-2 m
Explanation
The potential difference is related to the electric field by:
(1)
where
is the potential difference
E is the electric field
d is the distance
We want to know the distance the detectors have to be placed in order to achieve an electric field of

when connected to a battery with potential difference

Solving the equation (1) for d, we find

When gases, fluids, or other solids are in contact with a moving object
heat is produced due to friction.
Explanation:
Given that,
Length of gold wire, l = 4 m
Voltage of battery, V = 1.5 V
Current, I = 4 mA
The resistivity of gold, 
Resistance in terms of resistivity is given by :

Also, V = IR
So,

A is area of wire,
, r is radius, r = d/2 (diameter=d)

Out of four option, near option is (C) 17 μm.
Answer:
The magnitude of angular acceleration is
.
Explanation:
Given that,
Initial angular velocity, 
When it switched off, it comes o rest, 
Number of revolution, 
We need to find the magnitude of angular acceleration. It can be calculated using third equation of rotational kinematics as :
So, the magnitude of angular acceleration is
. Hence, this is the required solution.