repeated mesurement can reduce the error
it is true
if you take any mesurement repeatedly and the average is taken, the error will be less
Answer:
140265.8 C = 1.403 × 10⁵ C
Explanation:
The battery's electric potential energy is used to account for the kinetic and potential work done in moving the car up this hill.
Potential work required to move the 757 kg car up a vertical height of 195 m = mgh
P.E = 757 × 9.8 × 195 = 1446627 J
Kinetic work done = (1/2)(m)(v²)
K.E = (1/2)(757)(25²) = 236562.5 J
Total work done in moving the car up that height = 1446627 + 236562.5 = 1683189.5 J
And this would be equal to the potential of the battery.
For the battery, potential difference = (electric potential energy)/(charges moved)
ΔV = ΔU/q
q = ΔU/ΔV
ΔU = 1683189.5 J
ΔV = 12.0 V
q = 1683189.5/12 = 140265.8 C
Answer:
3.24×10⁸ J, or 324 MJ
Explanation:
"kWh" is a kilowatt-hour. It's the energy used by 1 kilowatt of power after one hour.
A kilowatt is a kilojoule per second.
90 kWh
= 90 kW × 1 hr
= 90 kJ/s × 1 hr
= 90 kJ/s × 3600 s
= 324,000 kJ
= 324,000,000 J
The energy is 3.24×10⁸ J, or 324 megajoules.