+91-87964 74404
FlagBACK
Question icon
Grade 11Mechanics

A motor rotating at 500 rpm is switched off. It comes to rest in 10 seconds. Find the angular retardation and the number of revolutions made by it before stopping.

Profile image of Adil Majeed
11 Years agoGrade 11
Answers icon

1 Answer

Profile image of Shobhit Varshney
11 Years ago
Hi,

Given , wo= 500 rpm = 500 /60 rotations per second = 25/3 rps
time = 10 seconds

So, w = 0 = wo+\alphat,
\alpha= – 25/ 30 rotations / s2= -5/6 rotations / s2

Now,\Theta= wo t+ 0.5\alphat2

So,\Theta= (25/3) 10 + 0.5 (-5/6) 102= 125/3 rotations.

thanks

Other Related Questions on mechanics

question mark

Three identical balls are placed on a frictionless horizontal surface touching each other. They stick to each other because of adhesive. Another ball of same radius and mass m is placed over the void created by the three balls. Find the forces applied by the balls kept on the floor to each other if the system remains in equilibrium.

mechanics
1 Answer Available

Last Activity: 9 Months ago

question mark

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.


11

21

31

41

mechanics
1 Answer Available

Last Activity: 10 Months ago

question mark
A metal strip clamped at one end vibrates with a frequency of 20 Hz and amplitude of 5 mm
at the free end, where a small mass of 2 g is positioned. determine
(i) The velocity of the end when passing through the zero position
(ii) The acceleration at maximum displacement
(iii) The maximum kinetic energy of the mass
mechanics
2 Answers Available

Last Activity: 3 Years ago

question mark
An object of mass m = 0.25 kg oscillates in a fluid at the end of a vertical spring of spring
constant kH = 85 N/m, see Fig.1. The effect of the fluid resistance is governed by the
damping constant b = 0.07kg/s.
(i) Find the period of the damped oscillation.
(ii) By what percentage does the amplitude of the oscillation decrease in each cycle? 
mechanics
1 Answer Available

Last Activity: 3 Years ago

question mark
If a=x² find the displacement at t =3sec if body velocity at t= 0 sec is 0
mechanics
1 Answer Available

Last Activity: 3 Years ago