Answer:
40 m/s
Explanation:
given,
height of the fall, h = 82 m
time taken to fall, t = 1.3 s
rock velocity, v = ?
acceleration due to gravity, g = 9.8 m/s²
rock is released initial velocity, u = 0 m/s
using equation of motion
v² = u² + 2 a s
v² = 0 + 2 x 9.8 x 82
v² = 1607.2
v = 40 m/s
hence, rock's velocity is equal to 40 m/s
Yes that's a true statement. That's why grandmother put a hot water bottle to warm up her bed, and not a hot bar of steel or lead.
I think the answer is repulsive.... Sorry if I get this wrong? :)
Answer:
1 * 10^-7 [J]
Explanation:
To solve this problem we must use dimensional analysis.
1 ergos [erg] is equal to 1 * 10^-7 Joules [J]
![1[erg]*\frac{1*10^{-7} }{1}*[\frac{J}{erg} ] \\= 1*10^{-7}[J]](https://tex.z-dn.net/?f=1%5Berg%5D%2A%5Cfrac%7B1%2A10%5E%7B-7%7D%20%7D%7B1%7D%2A%5B%5Cfrac%7BJ%7D%7Berg%7D%20%5D%20%5C%5C%3D%201%2A10%5E%7B-7%7D%5BJ%5D)
Firstly, do you understand the concept of a wavelength?