Question

Шарик массой 100 г,привязанный к нити движется в вертикальной плоскости по окружносьи радиусом 30.см 1.найти с какой силой натянута нить в тот момент когда шарик проходит верхние положение,если он двидется со скоростью 210 см/с 2.с какой силой натянута нить когда шарик проходит верхнее положение

Answer 1

I can try to answer your question in detail. The ball with a mass of 100 g, tied to a thread, moves in a vertical plane along a circle with a radius of 30 cm.

1. To find the force with which the thread is stretched at the moment when the ball passes the upper position, if it moves with a speed of 210 cm/s, we can use the following formula:

$$T - mg = m \frac{v^2}{R}$$

where T is the tension force, m is the mass of the ball, g is the acceleration due to gravity, v is the speed of the ball, and R is the radius of the circle.

Substituting the given values, we get:

$$T - 0.1 \times 9.8 = 0.1 \times \frac{(2.1)^2}{0.3}$$

Solving for T, we get:

$$T = 1.47 \text{ N}$$

Therefore, the force with which the thread is stretched at the upper position is 1.47 N.

2. To find the force with which the thread is stretched when the ball passes the lower position, we can use the same formula, but with a different sign:

$$T + mg = m \frac{v^2}{R}$$

Substituting the given values, we get:

$$T + 0.1 \times 9.8 = 0.1 \times \frac{(2.1)^2}{0.3}$$

Solving for T, we get:

$$T = 0.53 \text{ N}$$

Therefore, the force with which the thread is stretched at the lower position is 0.53 N.

I hope this helps you understand the problem. You can also check some similar problems and solutions on the web .