Answer:
6.3m/s
Explanation:
Given parameters:
Mass of the ball = 0.5kg
Height = 2m
Unknown:
Velocity when the ball hits the ground = ?
Solution:
Since the potential energy is transformed into kinetic energy;
P.E = K.E
mgh = m v²
cancelling m;
gh = v²
v² = 2gh
v = √2gh
Insert the parameters and solve;
v = √2gh = √ 2 x 9.8 x 2 = 6.3m/s
Answer:
25 m/s
Explanation:
First of all, we can find the acceleration the object by using Newton's second law of motion:
where
F = 20.0 N is the net force applied on the object
m = 4.0 kg is the mass of the object
a is its acceleration
Solving for a, we find
Now we know that the motion of the object is a uniformly accelerated motion, so we can find its final velocity by using the following suvat equation:
where
v is the final velocity
u = 0 is the initial velocity
is the acceleration
t = 5 s is the time
By substituting,