C. The person's feet push backward on the sidewalk; the sidewalk pushes forward on the person.
This is due to our kick back motion forced on the sidewalk when we walk, and the resistance of us walking on it createsa push forward.
Hope this helps!
Answer:
The maximum temperature rise = 0.047 °C
Explanation:
Potential Energy, P = mgh
Energy transfered, Q=mcΔT
Potential energy = Energy transfered
mgh = mcΔT
gh = cΔT
ΔT = gh/c
ΔT = (9.81 * 20) / 4186
ΔT = 0.047 °C
Explanation:
By Hooke's Law,
F=kx
The only force acting here is weight, and x is the extension of the string (you need to convert this to mm) so
mg=kx
(0.15)(9.81)=k ((420-300)x10^-3)
Then just solve this equation.
Answer:
15
Explanation:
P=W/T
T=6sec
W=?
F=60N
S=18m
W=F X S. .s indicate displacement
W=60x18
W=108
So p=108 j/6sec
P=15watt