The answer is 3.
When a ball is thrown into the air, there is no friction (there's nothing rubbing against it), so the only force acting on the ball is gravity, which aims to pull the ball back down. Since this is the only force, the answer will equal the gravity acting on the ball. Since "weight" is defined as just that (the gravity acting on something), the answer is 3, the magnitude of the rock's weight (or the force of gravity).
Answer:
Minimum speed will be equal to 2.213 m/sec
Explanation:
We have given radius of the r = 2 m
Coefficient of friction
At minimum speed frictional force will be equal to centripetal force
So
So the minimum speed will be equal to 2.213 m/sec
The answer is B hope I helped
Answer:
- Momentum is conserved
- Some kinetic energy is converted into thermal energy
Explanation:
Collision occurs when an object exert force on another. Collision can either be elastic or inelastic depending on whether the bodies stick together or separates after collision.
For elastic collision, the bodies separates after collision and due to this both their momentum and energy are conserved. Both separated object doesn't loose energy as such during collision and they possesses greater momentum.
In inelastic collision, the bodies stick together after collision. Their momentum is conserved but not their kinetic energy since they are not free to move independently.
Based on the question, the type of collision that occur is an inelastic collision since they stick together in air after collision. Some of the kinetic energy of the particles are turned into vibrational energy of the atoms leading to heating effect. Based on this, the following are true
- Their momentum before and after collision is conserved
- Some kinetic energy is converted into thermal energy(heat)
When object reached the terminal speed then its acceleration is zero
So as per Newton's II law we can say
now in that case we can say that net force is zero so here weight of the object is counter balanced by the drag force when it will reach at terminal speed
so we can write
so here we are given that
so terminal speed will be nearly 2 m/s