Grade 12th passMechanics

a force F=5t is applied on a lock of mass 10kg kept on rough horizontal surface (coefficient of friction =0.5),in rest what is speed of block at=20s?
1)15m/s ,2)18m/s,3)25m/s,4)can't be calculated

Anwesha Chakraborty

10 Years agoGrade 12th pass

3 Answers

Vikas TU

10 Years ago

acceleartion = (F-uN)/m =(5t – 0.5 * 100)/10 = (5t – 50)/2 m/s^2

a = dv/dt =(5t – 50)/2 m/s^2

dv = [(5t – 50)/2]dt

integerating both sides,

v = 5t^2/4 – 25t

at t=20s

put te value nd get d ansr.

Anwesha Chakraborty

10 Years ago

Well I tried it out the same way that you have done...and putting the value of t=20 I am getting 0...but answer is given to be 18m/s!

Puja Sahu

8 Years ago

at my end answer is 25m/s so I also think the answer is D – cannot be calculated... I tried every possible way but not getting any answer......................................................

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: 10 Months ago

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

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

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

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

View all Questions

a force F=5t is applied on a lock of mass 10kg kept on rough horizontal surface (coefficient of friction =0.5),in rest what is speed of block at=20s?1)15m/s ,2)18m/s,3)25m/s,4)can't be calculated

Anwesha Chakraborty

3 Answers

Vikas TU

Anwesha Chakraborty

Puja Sahu

Other Related Questions on mechanics

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.11213141

If a=x² find the displacement at t =3sec if body velocity at t= 0 sec is 0

a force F=5t is applied on a lock of mass 10kg kept on rough horizontal surface (coefficient of friction =0.5),in rest what is speed of block at=20s?
1)15m/s ,2)18m/s,3)25m/s,4)can't be calculated

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