Answer:
mass of the body is constant as it is property of body, but weight is product of acceleration due to gravity and mass, which may vary from place to place because acceleration due to gravity is different for different places.
Answer:
time taken with speed 23 km/h will be 1.8 hours or 1 hour 48 minutes
Explanation:
Given:
Time is inversely proportional to the speed
mathematically,
t ∝ (1/r)
let the proportionality constant be 'k'
thus,
t = k/r
therefore, for case 1
time = 3 hr
speed = 14 km/hr
3 = k/14
also,
for case 2
let the time be = t
r = 23 km/h
thus,
we have
t = k/23
on dividing equation 2 by 1
we get

or

or
t = 1.8 hr = or 1 hour 48 minutes ( 0.8 hours × 60 minutes/hour = 48 minutes)
Answer: Option (c) is the correct answer.
Explanation:
The difference in electrical potential energy between two places in an electric field is known as potential difference.
Mathematically, potential difference between two given points can be written as follows.

where,
= potential difference
= potential at point 1
= potential at point 2
Answer:
0.2932 rad/s
Explanation:
r = Radius = 2 m
= Initial angular momentum = 
= Initial angular velocity = 14 rev/min
= Final angular momentum
= Final angular velocity
Here the angular momentum of the system is conserved

The final angular velocity is 0.2932 rad/s