An athlete needs to lose weight and decides to do it by “pumping iron.” (a) How many times must an 90.0 kg weight be lifted a di
1 answer:
You might be interested in
Answer:
we can see that this time period is independent of the mass of the child so answer would be same if the child mass is different
Explanation:
Natural frequency of a simple pendulum of L length is given as
so the time period of the oscillation is given as
so we will have
also from above formula we can see that this time period is independent of the mass of the child so answer would be same if the child mass is different
(a)
The work-energy theorem states that the work done on the cheetah is equal to its change in kinetic energy:
where
m = 51.0 kg is the mass of the cheetah
u = 0 is the initial speed of the cheetah (zero because it starts from rest)
u = 31.7 m/s is the final speed
Substituting, we find
(b) 6.1 cal
The conversion between calories and Joules is
1 cal = 4186 J
Here the energy the cheetah needs is
Therefore we can set up a simple proportion
to find the equivalent energy in calories: