Answer:
Explanation:
Force needed to apply start the box is greater than the force needed to keep it moving because static friction is greater than the kinetic friction .
A threshold force is needed to move the box and when box started to move kinetic friction comes into play.
Friction force is directly related to the weight of the box as the friction force is
coefficient of friction time Normal reaction .
And Normal reaction is equal to the weight of box if no force is applied.
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Answer:
Electromagnetic waves are visible; mechanical waves are invisible. Electromagnetic waves always reflect; mechanical waves always refract.
Explanation:
Answer:
60°
Explanation:
It will be equilateral triangle, you can prove with the cosine theorem.
1)P^2=P^2+P^2 - 2×P×P× cos A
2) cos A= P^2 / 2× P^2 = 1/2
cos A = 1/2
A = 60°
If you wrote this question right,it will be solved like this :)