Grade 12Mechanics

A stationary bomb explodes into two parts of masses 3kg and 1kg. The total kinetic energy of the two parts after explosion is 2400 J. Then the K.E. of the smaller part is ?

ajay sharma

11 Years agoGrade 12

1 Answer

shabbir chatrissa

11 Years ago

the initial momentum is zero.

let m₁=3 kg m₂=1 kg & their velocities be v₁ & v₂ respectively.

according to conservationh of momentum

m₁v₁+ m₂v₂= 0

3v₁+ v₂= 0

v₂ = -3v₁

also,

0.5m₁v₂² + 0.5m₂v₂²= 24000

m₁v₁²+ m₂v₂²= 4800

3v₁² + v₂²= 4800

3v₁² +(-3v₁)²= 4800

12v₁² = 4800

v₁ = 20

v₂ = -60 (opp. direction)

KE of m₂ is 1800.

I suggest you still cross check.

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 stationary bomb explodes into two parts of masses 3kg and 1kg. The total kinetic energy of the two parts after explosion is 2400 J. Then the K.E. of the smaller part is ?

ajay sharma

1 Answer

shabbir chatrissa

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 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