Hi there!
We can use the work-energy theorem to solve.
Recall that:

The initial kinetic energy is 0 J because the crate begins from rest, so we can plug in the given values for mass and final velocity:

Now, we can define work:

Now, plug in the values:

Solve for theta:

Answer:
1÷60 h
time equals distance upon speed
The velocity of B after elastic collision is 3.45m/s
This type of collision is an elastic collision and we can use a formula to solve this problem.
<h3>Elastic Collision</h3>

The data given are;
- m1 = 281kg
- u1 = 2.82m/s
- m2 = 209kg
- u2 = -1.72m/s
- v1 = ?
Let's substitute the values into the equation.

From the calculation above, the final velocity of the car B after elastic collision is 3.45m/s.
Learn more about elastic collision here;
brainly.com/question/7694106
A superheated cloud of gas and dust swirling around a massive object (usually a black hole or neutron star) is called an accretion disk. The correct option is c.
<h3>What is accretion disk?</h3>
Accretion disk is a heavy object surrounded by flow of gas, plasma, dust, or particles. The materials surrounding the heavy object orbiting in the gravitational field of the object that loses energy and angular momentum as it slowly spirals inward.
This cloud can reach incredible speeds and temperatures as gravity causes it to build up more and more friction, eventually releasing x rays.
Thus, accretion disk is a superheated cloud of gas and dust swirling around a massive object.
Learn more about accretion disk.
brainly.com/question/1900229
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