Answer:
120 N
Explanation: First we shoud consider the forces acted on a tree
Friction foce - acting opposite to the moving direction
Weight - Directly acting downwards
Reaction - Directly acting on upwards
For minimum required force should be equal to the friction force
F = μ R
F = 0.5×480
= 120N
Water has a higher specific heat so it requires more energy to heat than sand.
Answer:
Explanation:
Given
mass of Projectile(m)=0.46 kg
Initial Kinetic Energy=1430 J
Maximum upward displacement from Launch point=150 m
v=78.85 m/s
and 
initial horizontal velocity
Initial vertical velocity
(c)vertical velocity at any instant=65 m/s
Since initial vertical velocity is 54.16 m/s
so 65 m/s will be acquired when projectile started falling below cliff
Answer:
Zero (0)
Explanation:
A horizontal line will be no movement of negative of positive acceleration
Answer:
50 N
Explanation:
Since the refrigerator doesn’t move, that means the force of friction equals the amount of force the child exerts on the fridge. If the friction force were greater than the force by the child, the fridge would start accelerating towards the child. If it were less than the force the child exerted, the fridge would start accelerating away from the child. Therefore, the net force must be 0, in this case, the friction force is equal to the force the child exerted, for it to stay at rest (as Newton’s First Law stated).
I hope this helps! :)
