Question

40 баллов!! 2. Теннисный Мяч (м=58 г) брошен вверх. Скорость броска 15м/с. A а) Определите кинетическую энергию мяча в момент его выпуска. б) Какую энергию высоты имеет мяч, если его скорость равна 10? в) На какой высоте мяч начнет падать? г) Какую максимальную высоту достигнет мяч?

Answer 1

Ответ:

ххщхщзщхзхшхщхщзззххззхззххззххх

Answer 2

А) 43.125 Дж
б) 29.0 Дж
в) 6 м
г) 7.5 м

Answer 3

Kinetic Energy of the Ball at Release

To determine the kinetic energy of the tennis ball at the moment of release, we can use the formula for kinetic energy:

Kinetic Energy (KE) = (1/2) * mass * velocity^2

Given: - Mass of the ball (m) = 58 g = 0.058 kg - Velocity of the throw (v) = 15 m/s

Substituting these values into the formula, we can calculate the kinetic energy:

KE = (1/2) * 0.058 kg * (15 m/s)^2

Calculating this expression gives us the kinetic energy of the ball at release.

Energy of the Ball at Height

To determine the energy of the ball at a certain height, we need to consider the conservation of mechanical energy. At any point during the ball's trajectory, the sum of its kinetic energy and potential energy is constant.

The potential energy of an object at a certain height is given by:

Potential Energy (PE) = mass * gravity * height

Given: - Mass of the ball (m) = 58 g = 0.058 kg - Velocity of the ball (v) = 10 m/s

We need to find the height at which the ball has this velocity. To do this, we can equate the kinetic energy and potential energy at that height:

(1/2) * mass * velocity^2 = mass * gravity * height

Simplifying the equation, we can solve for the height:

height = (1/2) * velocity^2 / gravity

Substituting the given values, we can calculate the height at which the ball has a velocity of 10 m/s.

Height at which the Ball Starts Falling

The height at which the ball starts falling can be determined by considering the point where the ball's potential energy is equal to zero. At this point, all of the ball's initial potential energy has been converted to kinetic energy.

Since the potential energy is given by:

Potential Energy (PE) = mass * gravity * height

Setting the potential energy equal to zero, we can solve for the height:

0 = mass * gravity * height

Simplifying the equation, we find that the height at which the ball starts falling is zero.

Maximum Height Reached by the Ball

To determine the maximum height reached by the ball, we can use the conservation of mechanical energy. At the highest point of its trajectory, the ball's kinetic energy is zero, and all of its initial energy is in the form of potential energy.

Using the formula for potential energy:

Potential Energy (PE) = mass * gravity * height

Setting the potential energy equal to the initial potential energy (which is equal to the kinetic energy at release), we can solve for the height:

(1/2) * mass * velocity^2 = mass * gravity * height

Simplifying the equation, we can solve for the height:

height = (1/2) * velocity^2 / gravity

Substituting the given values, we can calculate the maximum height reached by the ball.

Please note that the exact calculations for the values mentioned in the question cannot be provided as the necessary values for gravity and other constants are not given. However, you can use the formulas and the given values to perform the calculations yourself.