Answer: 18.35 m/s
Explanation:
At the highest point of trajectory, the vertical component of the velocity would be zero and the tennis ball would have horizontal component of velocity.
It is given that the initial velocity of the ball is 32 m/s and it makes 35° with the vertical. Hence the horizontal component of the velocity,
v sin θ = 32 m/s × sin 35° = 18.35 m/s
Hence, at the highest point in its trajectory, the tennis ball would be moving with the speed 18.35 m/s.
Initially, the spring stretches by 3 cm under a force of 15 N. From these data, we can find the value of the spring constant, given by Hook's law:

where F is the force applied, and

is the stretch of the spring with respect to its equilibrium position. Using the data, we find

Now a force of 30 N is applied to the same spring, with constant k=5.0 N/cm. Using again Hook's law, we can find the new stretch of the spring:
U can do what is the strongest paper towel
Answer:
Mechanical energy
Explanation:
A car changes chemical energy from fuel into thermal energy and mechanical energy.
Mechanical energy can be defined as the type of energy that is possessed by an object due to its motion or position. Mechanical energy is the sum of potential energy and kinetic energy, that is, the sum of energy in motion and stored energy. Examples of mechanical energy includes driving a car, riding a bicycle, listening to music etc.
Types of mechanical energy
1. Motion energy (kinetic energy)
2. Stored energy(potential energy)
Mechanical energy = Kinetic energy + Potential energy