Kinetic energy is related to velocity by:
KE = (1/2)mv^2
solve for mass m
10 = (1/2)m(10)^2
10 = (1/2)m(100)
10= 50m
10/50 = m
1/5 = m
at 20 km/hr
KE = (1/2)(1/5)(20)^2
KE = (1/10)(400)
KE = 40 J
Answer:
Net Force = 10N
Acceleration = 2m/s^2
Explanation:
calculate the net force and the acceleration on the block
Net force on the block F = mass * acceleration
Net force acting in the positive direction = 4N + 6N = 10N
Mass = 5kg
According to newton's second law;
a = F/m
a = 10N/5
a = 2m/s^2
hence the acceleration on the block is 2m/s^2
fraction equation is<span>
F =µR
F=friction,µ=coefficient , R=reaction = mg
use same equation for b part, but the reaction is no longer mg because the plain is now inclined. Draw a forces diagram and you will see that the reaction force can be calculated from the weight of the object and inclination of the plain using trigonometry.</span>