Answer: 2000 watts
Explanation:
Given that,
power = ?
Weight of object = 200-N
height = 4 m
Time = 4 s
Power is the rate of work done per unit time i.e Power is simply obtained by dividing work by time. Its unit is watts.
i.e Power = work / time
(since work = force x distance, and weight is the force acting on the object due to gravity)
Then, Power = (weight x distance) / time
Power = (200N x 4m) / 4s
Power = 8000Nm / 4s
Power = 2000 watts
Thus, 2000 watts of power is needed to lift the object.
Answer:
180,000
Explanation:
Frequency is a quantity that is measured in Hertz [Hz] and it represents the number of rotations per second.
A motor with a frequency of 50 Hz will rotate 50 times per second.
Since we don't want to know how many times it rotates per second, but per hour. The first step is to find how many seconds there are in an hour and then multiply that amount by 50.
Seconds in an hour:
there are 60 seconds per minute, and 60 minutes per hour, thus there are
60*60 = <u>3,600 seconds in an hour</u>
We know that the motor will rotate 50 times per second so to find the number of rotations in 1 hour = 3,600 seconds we multiply:
50*3,600 = 180,000 rotations
The added weight of the sand puts more downward pressure on the wheels contacting the rails, which would cause the trains speed to decrease.
How do you find instantaneous velocity
Select a point on a distance-time curve graph. Draw a tangent to the curve at that point. Tangent -> hypotenuse of right angled triangle. Opp/adjacent in graph units is vel at that point -> in distance and/or time
