Answer:
44 years
Explanation:
Use half life equation:
A = A₀ (½)^(t / T)
where A is the final amount,
A₀ is the initial amount,
t is time,
and T is the half life.
0.25 A₀ = A₀ (½)^(t / 22)
0.25 = (½)^(t / 22)
t / 22 = 2
t = 44
Yes, everything falling will make a sound unless it is air.
Answer:
Pedometers are designed to detect vertical movement at the hip and so measure the number of steps and provide an estimate of distance walked. They cannot provide information on the temporal pattern of physical activity or the time spent in different activity at different intensity.
Answer:
work done=fdcosø
f=mg=450N
d=+3m
ø=180
450×3×cos(180°) power=work done/
time taken
1350×-1 p=135watts
Answer:
Force exerted, F = 1.5 N
Explanation:
It is given that, a boxer punches a sheet of paper in midair and brings it from rest up to a speed of 30 m/s in 0.060 s.
i.e. u = 0
v = 30 m/s
Time taken, t = 0.06 s
Mass of the paper, m = 0.003 kg
We need to find the force the boxer exert on it. The force can be calculated using second law of motion as :
F = 1.5 N
So, the force the boxer exert on the paper is 1.5 N. Hence, this is the required solution.
