The correct option is b i.e none is correct.
The instantaneous velocity would be zero at the top but the acceleration would not be zero at that point. This is because the acceleration is the rate of change of velocity. since, the velocity is not constant, hence the acceleration would not be zero. The correct answer would be option b: None is correct.
d. the surface on which the object is moving is made smoother
This is called lubrication, I think ...
b. the weight of the moving object is decreased
If there is less araea of contact because of the weight reduction ("squeezing together") then this could also have an effexct. I thinl though the thrust of the q is on lubrication = oil, talcum powder, thin films of water etc
Please put answers in the comments of actual answers, as I need them! Lots of points! 63 points
Answer:
Given
mass (m) =2kg
velocity (v) =3m/s
momentum (p) =?
Form
p=mv
2kgx3m/s
p=6kg.m/s
the momentum of ball's =6kg.m/s
I believe is A) Inner core
Answer:
8 signals received by twin A during the trip.
Explanation:
Given that,
Distance = 12 light year
Speed = 0.6 c
Time = 1 year
We need to calculate the time by A
Using formula of time
Put the value into the formula
Similarly,
The expression for distance cover by A
We need to calculate the time
Using formula of time
We need to calculate the signals received by twin A
Using formula for number of signals
Put the value into the formula
Hence, 8 signals received by twin A during the trip.
