The correct answer is D: which is none of the above.
Hint: a wreckling ball contains pontential energy that acts like a pendulum
a pot of water contains pontential thermal energy
<span>we know energy = power*time(in hour)
so energy used by 1.20kw(1200 watt) toast oven used for 6.2 min(6.2/60 hour) =
1200*(6.2/60)=1200*0.103 = 124 watt hour.
Energy used by 11 w cfl used for 8.50 hour = (11*8) + (11* (50/60)) = 88+9.166=97.166 watt hour.</span>
Explanation:
a) Sum of moments about the pivot:
∑τ = Iα
(10 kg × 10 m/s²) (0.3 m) + F (-0.4 m) = 0
F = 75 N
b) Sum of moments about the pivot:
∑τ = Iα
(20 N) (0.3 m) + (20 N) (-0.2 m) + F (-0.7 m) = 0
6 Nm − 4 Nm + F (-0.7 m) = 0
F = 2.9 N
A. All natural radiation is at a level low enough to be safe
