Question

Тіло кинуто в горизонтальному напрямку з початковою швидкістю 15 м/с. Через скільки секунд кінетична енергія тіла збільшиться у 2 рази ?

Answer 1

через 1,5 сек скорость тела в вертикальном направлении также составит 15 м/с
полная кінетична енергія тіла збільшиться у 2 рази

Answer 2

Calculation of the Time Required for the Kinetic Energy to Double

To determine the time required for the kinetic energy of an object to double, we need to use the formula for kinetic energy:

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

Given that the initial velocity of the object is 15 m/s, we can assume the mass of the object to be constant. Let's denote the initial kinetic energy as KE1 and the final kinetic energy (when it doubles) as KE2.

According to the problem, we want to find the time it takes for the kinetic energy to double. Mathematically, this can be expressed as:

KE2 = 2 * KE1

Substituting the formula for kinetic energy, we have:

(1/2) * mass * velocity2^2 = 2 * (1/2) * mass * velocity1^2

Simplifying the equation, we find:

velocity2^2 = 4 * velocity1^2

Taking the square root of both sides, we get:

velocity2 = 2 * velocity1

Now, we can solve for the time required for the kinetic energy to double by using the equation for velocity:

velocity = distance / time

Since the body is thrown horizontally, we can assume that the distance traveled is constant. Therefore, we can rewrite the equation as:

velocity2 = distance / time2

velocity1 = distance / time1

Substituting the values, we have:

2 * velocity1 = distance / time2

velocity1 = distance / time1

Since the distance traveled is constant, we can equate the two equations:

2 * velocity1 = velocity1 / time2

Simplifying the equation, we find:

time2 = 1 / (2 - 1) = 1 second

Therefore, it will take 1 second for the kinetic energy of the object to double.