Explanation:
30 minutes is 1800 seconds.
Power = energy / time
P = 1100 J / 1800 s
P = 0.611 W
Converting the energy from J to kWh:
1100 J × (1 Ws / 1 J) × (1 kW / 1000 W) × (1 h / 3600 s) = 3.06×10⁻⁴ kWh
To find resistance, you need to be given either the voltage or the current.
Answer:
the length of stretched spring in cm is 22
Explanation:
given information:
spring length, x1 = 20 cm = 0.2 m
force, F = 100 N
the length of spring streches, x2 = 22 cm = 0.22 m
According to Hooke's law
F = - kΔx
k = F/*=(x2-x1)
= 100/(0.22 - 0.20)
= 5000 N/m
if the spring is now suspended from a hook and a 10.2-kg block is attached to the bottom end
m = 10.2 kg
W = m g
= 10.2 x 9.8
= 99.96 N
F = - k Δx
Δx = F / k
= 99.96 / 5000
= 0.02
Δx = x2- x1
x2 = Δx + x1
= 0.20 + 0.02
= 0.22 m
= 22 cm
Make the base of the building zero. Then the initial distance is 100m, final distance unknown x. Use gravity, time and initial velocity to solve for final distance.
x - 100 = (0)(5) +(1/2)(-9.81)(5^2)
x - 100 = 0 - 122.625
x = -122.625 + 100
x = -22.625 m below ground
A scientist would write that number as 1.49 x 10⁸ kilometers .
(Or, if the scientist is in France or the UK, he might write it as 1.49 x 10⁸ kilometres .)
