Answer:
Net force = 10 N in downward direction
Explanation:
Given that,
Upward force = 10 N
Downward force = 20 N
Let downward is negative and upward is positive.
Net force = 10+(-20)
= -10 N
So, the net force is 20 N and it is acting in downward direction.
I believe the answer is C. an increase in the number of cold climates
Answer:
Hans is more powerful
Explanation:
Power: This can be defined as the rate at which work is done or energy is used up.
The expression for power is given as,
P = E/t
P = mgh/t................. Equation 1
Where P = power, W = Work, t = time, m = mass, h = height, g = acceleration due to gravity.
Hans' power
P = mgh/t
Given: m = 100 kg, h = 2 m, g = 9.8 m/s², t = 3 s
Substitute into equation 1
P = 100(9.8)(2)/3
P = 653.33 W.
Frans' power
P' = mgh/t
Given; m = 200 kg, h = 5 m, t = 20 s.
P' = 200(5)(9.8)/20
P' = 9800/20
P' = 490 W
from the above,
since P>P'
Hence, Hans is more powerful
Answer:
0Nm, no work is done.
Explanation:
Work done is defined as the Force per distance meaning force times the distance moved in the direction of the force.
Now the body of mass 50g has a centripetal force acting on it directed towards the centre. Now in actuality the body stays along the circle it doesn't really move to the centre of the circle.
Hence the force doesn't move a distance, and so from the definition of work done;
F×d ; d =0
Hence work done = mv2/r × 0= 0Nm
Answer:
Explanation:
Newton's first law of motion:
An object in motion stays in motion, and an object at rest stays at rest, until acted upon by an unbalanced force.
Newton's second law:
The net force on an object is equal to its mass times its acceleration.
Newton's third law:
For every action, there is an opposite and equal reaction.
