Answer:
final kinetic energy of the hammer is 10 kJ
Explanation:
As we know that there is no non conservative force on the system
So here we can use the theory of mechanical energy conservation
So we will have

here we know that

from above expression now


so final kinetic energy of the hammer is 10 kJ
Answer:
Dear user,
Answer to your query is provided below
Acceleration is zero because of no change in velocity.
Explanation:
Remember that velocity is a vector quantity and a vector can change in 3 ways
•Magnitude only
•Direction only
•Both magnitude and direction.
Now the magnitude of velocity (speed) can stay constant while the direction is changing. This is the case in circular motion.
In the question above, it is mentioned that the girl is moving along a straight road. Therefore no change in direction of velocity.
Answer:
The initial velocity is 50 m/s.
(C) is correct option.
Explanation:
Given that,
Time = 10 sec
For first half,
We need to calculate the height
Using equation of motion

....(I)
For second half,
We need to calculate the time
Using equation of motion



Put the value of h from equation (I)


According to question,


Put the value of t₁ and t₂



Here, g = 10
The initial velocity is


Hence, The initial velocity is 50 m/s.
False the North Star never changes it position