Answer:
E = 0.4 kWh
Explanation:
Given that,
The power of a bulb, P = 40 W
Time, t = 10 hours
We need to find the energy used by the bulb. Let it is equal to E. So,
![E=P\times t\\\\E=40\times 10\\\\E=400\ W-h\\\\or\\\\E=0.4\ kWh](https://tex.z-dn.net/?f=E%3DP%5Ctimes%20t%5C%5C%5C%5CE%3D40%5Ctimes%2010%5C%5C%5C%5CE%3D400%5C%20W-h%5C%5C%5C%5Cor%5C%5C%5C%5CE%3D0.4%5C%20kWh)
So, 0.4 kWh of energy would be needed.
Answer:
cannot do diagrams on here sorry :)
The magnitude of the resultant momentum can be calculated using the following rule:
p = sqrt [(px)^2 + (py)^2]
px is given to be 100 kg m/sec
py is given to be 98 kg m/sec
Substitute in the above equation to calculate the magnitude of the resultant momentum as follows:
p = sqrt[(100)^2+(98)^2]
p = 140 kg m/sec