Question

Шар массой 2кг движется со скоростью 5м/с навстречу шару массой З кг, движущемуся со скоростью 10м/с. Найти величину изменения кинетической энергии системы шаров после неупругого центрального удара.

Answer 1

Ответ:

• величина 3 10:5=2 2-3=1 2+1=3

Answer 2

Calculation of the Change in Kinetic Energy

To find the change in kinetic energy of the system of two balls after an inelastic central collision, we need to calculate the initial and final kinetic energies and then find the difference.

Given: - Mass of the first ball (m1) = 2 kg - Initial velocity of the first ball (v1) = 5 m/s - Mass of the second ball (m2) = 3 kg - Initial velocity of the second ball (v2) = -10 m/s (since it is moving in the opposite direction)

To calculate the initial kinetic energy (KEi) of the system, we use the formula:

KEi = 0.5 * m1 * v1^2 + 0.5 * m2 * v2^2 Substituting the given values:

KEi = 0.5 * 2 * (5)^2 + 0.5 * 3 * (-10)^2

Simplifying the equation:

KEi = 0.5 * 2 * 25 + 0.5 * 3 * 100

KEi = 25 + 150

KEi = 175 Joules

Now, let's calculate the final kinetic energy (KEf) of the system after the collision. Since it is an inelastic collision, the two balls stick together and move with a common velocity (vf).

To find vf, we can use the principle of conservation of momentum, which states that the total momentum before the collision is equal to the total momentum after the collision.

m1 * v1 + m2 * v2 = (m1 + m2) * vf Substituting the given values:

2 * 5 + 3 * (-10) = (2 + 3) * vf

Simplifying the equation:

10 - 30 = 5 * vf

-20 = 5 * vf

vf = -4 m/s

Now, we can calculate the final kinetic energy (KEf) using the formula:

KEf = 0.5 * (m1 + m2) * vf^2

Substituting the given values:

KEf = 0.5 * (2 + 3) * (-4)^2

Simplifying the equation:

KEf = 0.5 * 5 * 16

KEf = 40 Joules

Finally, we can find the change in kinetic energy (ΔKE) by subtracting the initial kinetic energy (KEi) from the final kinetic energy (KEf):

ΔKE = KEf - KEi

Substituting the calculated values:

ΔKE = 40 - 175

ΔKE = -135 Joules

Therefore, the change in kinetic energy of the system of two balls after the inelastic central collision is -135 Joules.

Note: The negative sign indicates a decrease in kinetic energy.