# Physic

A 60-g bullet fired at two blocks resting on a surface with coefficient of kinetic friction =0.5.
The bullet pass through a 8-kg block and make this block slides 0.8 m.
And then the bullet lodges in another block which is 6 kg. The bullet make it slides 1.2 m.

Here is where i got lost, i list two equation:
m-mass of bullet
M-mass of 8-kg block
Vi-initial velocity of bullet
Vf-final velocity of the bullet & 8-kg-block
fk-frictional force acting on the bullet & 8-kg-block

m*Vi=(m+M)Vf
1/2(m+M)(Vf)^2=fk*d

I think all the work of the frictional force equals to the energy provided to the block by the collision
Where did i go wrong?

1. 👍 0
2. 👎 0
3. 👁 258
1. Collision is inelastic
Energy cannot be conserved!!!

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Impulse and Momentum

A bullet of mass m is fired at speed v0 into a wooden block of mass M. The bullet instantaneously comes to rest in the block. The block with the embedded bullet slides along a horizontal surface with a coefficient of kinetic

asked by Jennifer on March 1, 2015
2. ### physics

A light spring with force constant 3.85 N/m is compressed by 5.00 cm as it is held between a 0.250 kg block on the left and a 0.500 kg block on the right, both resting on a horizontal surface. The spring exerts a force on each

asked by Jessi on February 24, 2009

2 blocks are connected by a rope of negligible mass are being dragged by a horizontal force. Suppose F= 68.0N, m1= 12.0kg, m2= 18.0kg and the coefficient of kinetic friction between each block and the surface is 0.100. a.) draw

asked by ~christina~ on October 17, 2007
4. ### phys

Two blocks of mass m1 = 1.70 kg and m2 = 5.20 kg are connected by a massless cord passing over a frictionless pulley as shown in the figure below, with θ = 41.0°. The coefficient of kinetic friction between block 1 and the

asked by victpr on October 1, 2016
5. ### Physics

A 12 g bullet is fired horizontally into a 96 g wooden block initially at rest on a horizontal surface. After impact, the block slides 7.5 m before coming to rest. If the coefficient of kinetic friction between block and surface

asked by Nicole on January 5, 2012
1. ### physics

A 25 g bullet is fired from a gun into a 1.35 kg block of wood initially at rest. (The bullet sticks in the wood). The wood is driven 9.5 m across a horizontal surface with coefficient of friciton 0.25. Find the speed of the

asked by ashley on November 30, 2012
2. ### Physics

A 3.5 g bullet is fired horizontally at 2 blocks resting on a smooth tabletop. The bullet passes trough the 1st block, with mass 1.2 kg and embed itself in the second with mass 1.8 kg. Speeds of 0.63 m/s and 1.4 m/s, respectively

asked by Jo Wan on October 26, 2018
3. ### Physics

A 50g bullet strikes a stationary 1.50kg block of wood paced on a horizontal surface just in front of the gun. The bullet becomes embedded in the block and the impact drives them a distance of 10m before they come to rest. If the

asked by Sarah on May 9, 2012
4. ### physics

A 30.0-kg block is resting on a flat horizontal table. On top of this block is resting a 15.0-kg block, to which a horizontal spring is attached, as the drawing illustrates. The spring constant of the spring is 340 N/m. The

asked by Donna on November 26, 2013
5. ### Physics

A 15.0 gram bullet strikes and becomes embedded in a 1.24 kg block of wood placed on a horizontal surface just in front of the gun. If the coefficient of kinetic friction between the block and the surface is 0.280, and the impact

asked by Alexis on January 5, 2011
6. ### physics

A 14 g bullet is ﬁred into a 120 g wooden block initially at rest on a horizontal surface. The acceleration of gravity is 9.8 m/s^2 . After impact, the block slides 6.97 m before coming to rest.If the coeﬃcient of friction