Donald trump is 74 years old
Answer:
a) 2.85 kW
b) $ 432
c) $ 76.95
Explanation:
Average price of electricity = 1 $/40 MJ
Q = 20 kW
Heat energy production = 20.0 KJ/s
Coefficient of performance, K = 7
also
K=(QH)/Win
Now,
Coefficient of Performance, K = (QH)/Win = (QH)/P(in) = 20/P(in) = 7
where
P(in) is the input power
Thus,
P(in) = 20/7 = 2.85 kW
b) Cost = Energy consumed × charges
Cost = ($1/40000kWh) × (16kW × 300 × 3600s)
cost = $ 432
c) cost = (1$/40000kWh) × (2.85 kW × 200 × 3600s) = $76.95
Answer:
240 V
Explanation:
number of turns in primary coil, Np = 10
Number of loops in secondary coil, Ns = 20
Voltage in primary coil, Vp = 120 V
Let the voltage in secondary coil is Vs.
So, Vs / Vp = Ns / Np
Vs / 120 = 20 / 10
Vs / 120 = 2
Vs = 240 V
Thus, the voltage in secondary coil is 240 Volt.
Answer:
2081.65 m
Explanation:
We'll begin by calculating the time taken for the load to get to the target. This can be obtained as follow:
Height (h) = 3000 m
Acceleration due to gravity (g) = 10 m/s²
Time (t) =?
h = ½gt²
3000 = ½ × 10 × t²
3000 = 5 × t²
Divide both side by 5
t² = 3000 / 5
t² = 600
Take the square root of both side
t = √600
t = 24.49 s
Finally, we shall determine the distance from the target at which the load should be released. This can be obtained as follow:
Horizontal velocity (u) = 85 m/s
Time (t) = 24.49 s
Horizontal distance (s) =?
s = ut
s = 85 × 24.49
s = 2081.65 m
Thus, the load should be released from 2081.65 m.
The period of one full swing depends on the length of the pendulum and on gravity. The period of each full swing would be longer on the moon, with less gravity.
The rotation of the plane of the swings doesn't depend on the length of the string OR on gravity. It only depends on the latitude of the place where the pendulum hangs, and the rotation period of the body it's located on.
On Earth, it's (24 hours)/(sine of latitude).
On the moon, it would be (27.32 days)/(sine of latitude).
