Answer:
The work done on the box is 100 Nm
The power is 20 Nm/s
Explanation:
There is a force 25 newtons moves a box a distance of 4 meters in
5 seconds
The work done on the box is the product of the force and the distance
that the box moves ⇒ <em>work = force × distance</em>
The force = 25 newtons
the distance = 4 meters
Work = 25 × 4 = 100 NM
<em>The work done on the box is 100 Nm</em>
<em></em>
The force moves the box 4 meters in 5 seconds
The power is the rate of work
<em>The power = work ÷ time</em>
The work = 100 Nm
The time = 5 seconds
The power = 100 ÷ 5 = 20 Nm/s
<em>The power is 20 Nm/s</em>
Solution :
Given
Diameter of the roulette ball = 30 cm
The speed ball spun at the beginning = 150 rpm
The speed of the ball during a period of 5 seconds = 60 rpm
Therefore, change of speed in 5 seconds = 150 - 60
= 90 rpm
Therefore,
90 revolutions in 1 minute
or In 1 minute the ball revolves 90 times
i.e. 1 min = 90 rev
60 sec = 90 rev
1 sec = 90/ 60 rec
5 sec = 
= 75 rev
Therefore, the ball made 75 revolutions during the 5 seconds.
The surface temperature of the star increases when it changes its colour changes from red to blue.
Blue>white>yellow>orange>red
The given series is the temperature decreasing order of stars. Now our sun is considered as a yellow star.
Answer:
5.88×10⁸ W
Explanation:
Power = change in energy / time
P = mgh / t
P = (m/t) gh
P = (1.2×10⁶ kg/s) (9.8 m/s²) (50.0 m)
P = 5.88×10⁸ W
Explanation:
that's impossible,the radius of the earth can't decrease when the mass doubles!
