Answer:
8.953 s
Explanation:
Here a time of 8953 ms is given.
Some of the prefixes of the SI units are
mili = 10⁻³
micro = 10⁻⁶
nano = 10⁻⁹
kilo = 10³
Mega = 10⁶
Each prefix increases or decreases by a factor of 10³
The number is 8953.0
Here, the only solution where the number of significant figures is mili. If any other prefix is chosen then the significant figures will increase.
So, 8953 ms = 8.953 s
Answer:
6.16 m/s
0.0105 m
Explanation:
Let the ground 0 for potential reference be at where the spring is compress 0.24 m. The the man would jump from a height h = 2.5 + 0.24 = 2.74 m from it. We can apply the law of energy conservation knowing that as the man jumps, his potential energy converts to kinetic energy, then finally to elastic energy:
where m = 80 kg is the man mass, g = 9.81 m/s2 is the gravitational acceleration, h = 2.74 m is the potential distance he travels, k N/m is the spring constant and x = 0.24 is the distance it compresses
Similarly at the position where it compresses by 0.12 m, it's 0.24 - 0.12 = 0.12 m far from ground 0.
When he steps gently, then his gravity force would equal to his spring force