A bullet of mass 25.0g is fired with a horizontal velocity of 240.0ms^-1 from a gun of mass 4.0kg.
a) Calculate the initial velocity of the gun.
(0.025kg)(240 ms^-1) - (4U) = 0
6 - 4U = 0
6 = 4U
U = 1.5 ms^-1
b) The bullet strikes the stationary block of wood of mass 550.0g soon after leaving the gun and becomes embedded in it. Calculate the velocity with which the block and bullet start to move.
Momentum before = momentum after
(0.025 X 240) = 0.550025V
V = 6 / 0.550025
V = 10.9 ms^-1
Is this correct? Help would be appreciated if not, and helpful responses will receive 10 points!
a) Calculate the initial velocity of the gun.
(0.025kg)(240 ms^-1) - (4U) = 0
6 - 4U = 0
6 = 4U
U = 1.5 ms^-1
b) The bullet strikes the stationary block of wood of mass 550.0g soon after leaving the gun and becomes embedded in it. Calculate the velocity with which the block and bullet start to move.
Momentum before = momentum after
(0.025 X 240) = 0.550025V
V = 6 / 0.550025
V = 10.9 ms^-1
Is this correct? Help would be appreciated if not, and helpful responses will receive 10 points!
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You should keep units on your intermediate calculations. Where did this come from?
0.550025
I think you were trying to add 25.0g and 550.0g and got that (presumably in kg). But that's incorrect. It would be 575g or 0.575kg.
a) is correct. When you fix your combined mass you should have the correct answer for b).
0.550025
I think you were trying to add 25.0g and 550.0g and got that (presumably in kg). But that's incorrect. It would be 575g or 0.575kg.
a) is correct. When you fix your combined mass you should have the correct answer for b).