<span>At an instant when the displacement is equal to a/2,
Potential energy U = 1/2ka(square) where a is displacement.
when a= a/2
U = 1/4ka(square)
U = E/4
Potential Energy = 1/4 Total energy</span>
<span>A particular frost-free refrigerator uses about 710kWh of electrical energy per year. You are to express this amount of energy in J, kJ, & Calories.
1 year (365 days / 1 year)(24 hours / 1 day)(3600s / 1h) = 31,536,000s
710 kWh/yr (1 yr) = 710 kWh
710 x 10^3 Wh = </span>710 x 10^3(J/s)(31,536,000s)<span> = 2.24 x 10^13 J
</span>2.24 x 10^13 J = 2.24 x 10^10 kJ = 5.35 x 10^12 cal
Answer:
I'm not sure but I think it's 35-39
1) Vf = Vo - gt; Vf = 0 => Vo = gt = 9.8m/s^2 * 1.5s = 14.7 m/s
2) d = Vo*t - gt^2 /2 = 14.7m/s*1.5 - 9.8m/s^2 * (1.5s)^2 / 2 = 11.02 m
^^^^^^^^^^^^^^^^^^^^^^^^^^^ is correct