This isExampleProblem #1.

Problem #1 is just like part a) below.1.) A 325 kg motorcycle is moving at 140 km/h, south.

a) Find its momentum.

b) At what velocity is the momentum of a 1754 kg car equal to that of the motorcycle?

This isExampleProblem #1.

Problem #2 is very similar.1.) A 325 kg motorcycle is moving at 140 km/h, south.

a) Find its momentum.

b) At what velocity is the momentum of a 1754 kg car equal to that of the motorcycle?

This isExampleProblem #1.

Problem #3 is very similar to part a) except you must solve for "m".1.) A 325 kg motorcycle is moving at 140 km/h, south.

a) Find its momentum.

b) At what velocity is the momentum of a 1754 kg car equal to that of the motorcycle?

This isExampleProblem #2.

Problem #4 is very similar.2.) Initially a soccer ball is going 23.5 m/s, south. In the end, it is traveling at 3.8 m/s, south.

The ball's change in momentum is 17.24 kg m/s, north. Find the ball's mass.

This isExampleProblem #2.

Problem #5 is very similar except you don't

need to rearrange the formula: Δ ρ = m ( v_{f}- v_{i}).2.) Initially a soccer ball is going 23.5 m/s, south. In the end, it is traveling at 3.8 m/s, south.

The ball's change in momentum is 17.24 kg m/s, north. Find the ball's mass.

This isExampleProblem #2.

Problem #6 is very similar except you

need to rearrange the formula: Δ ρ = m ( v_{f}- v_{i}) .

It becomes for v_{i}= [ Δ ρ - m v_{f}] / m2.) Initially a soccer ball is going 23.5 m/s, south. In the end, it is traveling at 3.8 m/s, south.

The ball's change in momentum is 17.24 kg m/s, north. Find the ball's mass.

This isExampleProblem #3.

Problem #7 uses the derived formula: Δ ρ = F_{Net}t

shown in part b) below. Use it to calculate Δ ρ .3.) A bobsled has a mass of 1.357 x 10

^{2}kg. A constant force is exerted on it for 5.42 s.

The sled's initial velocity is zero and its final velocity is 8.73 m/s, east.

a) What is its change in momentum?

b) What is the net force exerted on it?

This isExampleProblem #3.

Problem #8 is very similar.3.) A bobsled has a mass of 1.357 x 10

^{2}kg. A constant force is exerted on it for 5.42 s.

The sled's initial velocity is zero and its final velocity is 8.73 m/s, east.

a) What is its change in momentum?

b) What is the net force exerted on it?

In Problem #9, combine:

Δ ρ = m ( v_{f}- v_{i}) and Δ ρ = F_{Net}t

by setting Δ ρ = Δ ρ.

You will get: m ( v_{f}- v_{i}) = F_{Net}t

Then solve for: t

From previous work, we know that weight = F_{g}= mg and therefore m = F_{g}/ g.

In Problem #10, combine:

Δ ρ = m ( Δ v ) and Δ ρ = F_{Net}t

by setting Δ ρ = Δ ρ.

You will get: m ( Δ v ) = F_{Net}t

Then solve for: t

This isExampleProblem #4.

Problem #11 is very similar except

bothv_{B}and v'_{A}are equal to zero.4.) A 62.0 kg curler travelling at

^{+}1.72 m/s runs into a 78.1 kg curler and the 62.0 kg curler

comes to a stop. If the 78.1 kg curler was originally moving at^{+}0.85 m/s, find his velocity

after the interaction.

This isExampleProblem #4.

Problem #12 is very similar.4.) A 62.0 kg curler travelling at

^{+}1.72 m/s runs into a 78.1 kg curler and the 62.0 kg curler

comes to a stop. If the 78.1 kg curler was originally moving at^{+}0.85 m/s, find his velocity

after the interaction.

This isExampleProblem #4.

Problem #13 is very similar except

instead of v'_{A}= 0, this time v_{B}= 0.4.) A 62.0 kg curler travelling at

^{+}1.72 m/s runs into a 78.1 kg curler and the 62.0 kg curler

comes to a stop. If the 78.1 kg curler was originally moving at^{+}0.85 m/s, find his velocity

after the interaction.

Problem #14 is very similar to Problem #13 except

instead of v'_{A}being in the same direction as v_{A},

this time it is in the opposite.

Problem #15 is very similar to Problem #13 & 14

except this timeNONEof the velocities are zero.

(Be careful with the signs on each of the velocities.)

This isExampleProblem #5.

Problem #16 is very similar.5.) A 62.0 kg curler runs into a stationary 78.1 kg curler and they hold on to each other.

Together they move away at 1.29 m/s, west. What was the original velocity of the 62.0 kg curler?

This isExampleProblem #5.

Problem #17 is very similar.5.) A 62.0 kg curler runs into a stationary 78.1 kg curler and they hold on to each other.

Together they move away at 1.29 m/s, west. What was the original velocity of the 62.0 kg curler?

This isExampleProblem #6.

Problem #18 is very similar.6.) A 84.0 kg (total mass) astronaut in space fires a thruster that expels 35 g

of hot gas at 875 m/s. What is the velocity of the astronaut after firing the shot?

This isExampleProblem #6.

Problem #19 is very similar.6.) A 84.0 kg (total mass) astronaut in space fires a thruster that expels 35 g

of hot gas at 875 m/s. What is the velocity of the astronaut after firing the shot?

This isExampleProblem #6.

Problem #20 is very similar except

v_{A}& v_{B}≠ 0, instead v_{A}= v_{B}= 5.0 m/s and v'_{B}= 0.6.) A 84.0 kg (total mass) astronaut in space fires a thruster that expels 35 g

of hot gas at 875 m/s. What is the velocity of the astronaut after firing the shot?

This isExampleProblem #6.

Problem #21 is very similar.

v_{A}= v_{B}= 0

of hot gas at 875 m/s. What is the velocity of the astronaut after firing the shot?

Problem #22 is very tricky!

Given only:

Δ d_{xball}= 215 m

m_{cannon}= 4.5 kg

m_{cannon}= 225 kg

It doesn't seem like enough information!

Below isExampleProblem #7.

Problems #23, 24, 25, 26 are very similar.

There is asolution for #25.

In each case, you must analyze in both the x and y directions.

Determine which velocities = 0 to simplify the equations.

The magnitude of the resultant velocity, in each case,

will be found using the Pythagoreon Theorem.

The resultant angle will require Trig. [ θ = Tan^{-1}(y / x) ]7.) A 80.0 kg scrum-half moving south at 5.75 m/s runs into a stationary 97.0 kg full-back. The

scrum-half moves away at 4.62 m/s, 250^{o}. Find the velocity of the full-back after the interaction.

## Does this result make sense?

Click on drawing below.

Put

Momentumvectors tip to tail to Add.

Click on second drawing.

25.) A 1325 kg car moving north at 27.0 m/s collides with a 2165 kg car moving east at 17.0 m/s.

They stick together. What is their velocity after the collision?