9. A 0.25-kg mass is attached to a string and swung in a vertical circle whose radius is 0.75 m. At the bottom of the circle, the mass is observed to have a speed of 10 m/s. What is the magnitude of the tension in the string at that point

T =  33.34 N

Explanation:

Given that,

Mass attached to the spring, m = 0.25 kg

Radius of the vertical circle, r = 0.75 m

Speed of the mass, v = 10 m/s

We need to find the magnitude of the tension in the string at that point. We know that the tension in the string is equal to the centripetal force acting on it. It can be given by

So, the tension in the string is 33.34 N.

3. dark matter

empty space could also be a simple vacuum

the design of a ski jumping suit involves a trade-off between giving the skiers lift to get higher jumps and ensuring the skier does not face a lot of drag before the jump itself. an expansive suit may to lift the skier higher, but at the same time, it will also increase the air resistance. higher air resistance as the skier goes down the slope limits the speed of the jump. a big suit also increases the risk of losing balance or control, especially if there's a strong gust of wind. while technologically enhanced suits a lot, clothing is not the only factor in a ski jumper’s success. gathering speed while skiing down the slope, ensuring good speed on the ramp, and maintaining good body posture and form in the air all contribute to a ski jumper's success.