I belive it could be 6.5 but I could be wrong
If you write down the formula for friction, you will get an answer.
Ff = u * N Where N is a push down force that an object experiences.
u (mu) is a constant and has no units
It may not be accelerating and still experience friction. A is not correct.
Color and Density will not affect the frictional force. B is not so.
Buoyant forces are a different thing altogether. Generally friction has nothing to do with them. C is incorrect.
The last one is your answer. Technically mg should be the answer and not mass, but the second part is correct.
<u>Answer:</u>
Prior to exercise, a proper warm-up of 10-15 minutes is extremely important to avoid injuries.
- Don't go too hard in the beginning and boost your activity level slowly. A good indication of a proper warm-up is that you feel sweat on your body parts.
- Don't overstretch right in the beginning as it can cause sore in your muscles and joints or stress fractures.
- Take a break if you feel sick or fatigues and use other drinks along with water to replace electrolytes and body fluids.
From that particular list:
Mica (A), Quartz (B), and Copper (D) are minerals.
Steam (C) isn't.
We need to charge a metal sphere positively without touching it. This can be achieved using electrostatic induction.