4. A black cart with a mass of 2.0 kilograms and a white cart of unknown mass ar

Question

4. A black cart with a mass of 2.0 kilograms and a white cart of unknown mass are pushed toward one another with a spring between them and held motionless. When the carts are released the black cart rolls west at 5.0 meters per second while the white cart rolls east at 4.0 meters per second. Draw a set of arrows over each of the objects in the diagram below to show the direction of its velocity, write "v = 0" above any object that is not moving. a. before after b. Determine the mass of the white cart. 2.5 kg c. As the two carts are pushed apart, compared to the force on the white cart, the force on the black cart is: greater ii. smaller ii. the same

Explanation / Answer

A) the force on black cart is towards left and the force on white cart is towards right.

B): Since there is no external force which interrupted the motio, so momentum remains conserved i. e the momentum initially is equal to momentum finally.

Since it was at rest initially, so initial momentum is 0.

After they are released, let us assume that mass of white cart be m.

Solving the equation of momentum conservation we get

0=2kg*5m/s + mkg*(-4m/s) as velocity is opposite to velocity of first cart.

m=10/4

m=2.5.kg

C) :let us consider the motion for first one second

Velocity of black cart=5m/s and time=1s

Initial velocity =0m/s

So acceleration =5-0/1=5m/s²

Similarly accleration of white cart=4m/s²

force on black cart=mass*acceleration

=2*5=10N

Similarly force on white cart=mass * acceleration

=2.5*4=10N

Therefore the force on black cart is equal.

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.