Answer:
The magnitude of the force is 0.7255kN
Explanation:
The elevator floor acts on the person with a force that is due to the gravitational acceleration less the downward acceleration of the elevator:
(force of floor F) = (mass of person m) x [ (grav. acceleration g) - (elevator acceleration a) ]
in other words, considering the elevator floor as a reference frame in the Earth's gravitational field, the person's weight decreases due to the downward acceleration, as follows:
We are given the person's weight at rest, 0.9kN, from which the mass can be determined as:
So
200 Hz = 200 cycles per sec
<span>1 cycle, the period = 1/200 = 0.005 seconds, or 5 milli seconds.</span>
Answer: 249 seconds
Explanation:
Speed of bike = 2.52 m/s
Distance = 628 m
Time taken = ? ( let the unknown value be Z)
Recall that speed is the distance covered per unit time.
Hence, speed = Distance / Time taken
Time taken = Distance / speed
Z = 628m / 2.52 m/s
Z = 249.2 seconds (Round to nearest tenth i.e 249 seconds)
Thus, it takes 249 seconds for the girl to get to her friends house
Answer:
1) Assuming an adult person has an average mass of m=80 kg, and assuming it takes about 30 seconds to climb 5 meters of stairs, the energy used by the person is
So the power output is
And since the estimate we made is very rough, we can say that the power output of the person is comparable to the power output of the light bulb of 100 W.
2) Based on the results we found in the previous part of the exercise, since the power output of the person is comparable to the power output of 1 light bulb of 100 W, we can say that the person could have kept burning only one 100-W light bulb during the climb.
Explanation:
