Question

give reasons
Q2-3
Q3-1,2
tomorrow is my science sa pls tell it's urgent

Answer 1

Q2)

Ans 3} The materials that reduce friction are:

1.         Grease
2. Vaseline
3. Oil
4. Ball Bearings or other rolling objects
5. Lubricants

Q3)

Ans 1} Because gymnasts use a lot of equipment, it is crucial that the gymnast can hold onto the equipment as he or she performs the routines. A sweaty ring can cause accidents, so gymnasts use chalk to help absorb the sweat and gain a better, more reliable grip. Gymnasts will powder their hands, but some will also powder their hands when using equipment such as the high bar and uneven parallel bars.

Ans 2} School bags have wide straps because as we know larger surface area less force/thrust on it.Therefore they have wider stipes so that it doesn't give pain or stain to our shoulders.

Hope it helps... :)

Answer 2

Q2

A 3. Lubricants like oil,grease..

Ball bearing

Q 3

A 1. They apply chalk because to increase friction between their hands and the surface

Q 3. Bags have broad straps because when the area is greater the pressure is less.

So to reduce pressure bags have broad straps