Answer:
a) 0.31 rad/s
b) 100 J
c) 6.67 W
Explanation:
(a) the force would generate a torque of:

According to Newton 2nd law, the angular acceleration would be

It starts from rest, then after 15s it would achieve a speed of

(b) The distance angle swept by it is:

Hence the work by the child

c) Average power to work per time unit

Answer:
16000
Explanation:
Mass(m)=2Kg (1kg= 1ooo g then 2 kg=2000 g)
Velocity(v)= 4 meter
Acceleration due to gravity (g)=10m/s
We know that,
P.E= 1/2 mv^2
or, 1/2 × 2ooo × 4^2
or, 1/2×2000 ×16
or, 2000×8
Therefore= 16000
Answer:
yes
Explanation:
because when you slow down, the resistance slows with the speed.
Answer:
look at explanation
Explanation:
If heat rises, then why is it so cold at the top of a mountain? Heat does indeed rise. More specifically, a mass of air that is warmer than the air around it expands, becomes less dense, and will therefore float atop the cooler air. ... So when warm air rises, it cools off.
Answer:
Lifetime = 4.928 x 10^-32 s
Explanation:
(1 / v2 – 1 / c2) x2 = T2
T2 = (1/ 297900000 – 1 / 90000000000000000) 0.0000013225
T2 = (3.357 x 10^-9 x 1.11 x 10^-17) 1.3225 x 10^-6
T2 = (3.726 x 10^-26) 1.3225 x 10^-6 = 4.928 x 10^-32 s