Answer:
F = 47.6 N
Explanation:
- Newton's 2nd law can be expressed as the rate of change of the total momentum, respect of time, as follows:

- So, in order to find the average force exerted by the skater on the wall, we can find the change in momentum due to the force exerted by the wall (which is equal and opposite to the one exerted by the skater), and divide it by the time interval , as follows:

⇒ Fsk = 47.6 N (normal to the wall)
Answer:
(a) x0 = 0m and y0 = 49.0m
(b) Vox = 15.0m/s Voy = 0m/s
(c) Vx = Vo = 15.0m/s and Vy = -gt
(d) X = 15.0t and y = 49.0 - 4.9t²
(e) t = 3.16s
(f) Vf = 34.4m/s
Explanation:
Answer: KE = 62.5J
Explanation:
Given that
Mass of object = 5kg
kinetic energy KE = ?
velocity of object = 5m/s
Since kinetic energy is the energy possessed by a moving object, and it depends on the mass (m) of the object and the velocity (v) by which it moves. Therefore, the object has kinetic energy.
i.e K.E = 1/2mv^2
KE = 1/2 x 5kg x (5m/s)^2
KE = 0.5 x 5 x 25
KE = 62.5J
Thus, the object has 62.5 joules of kinetic energy.
Answer:
Option C
Maximum potential energy is at point R.
Explanation:
Potential energy is a product of mass, acceleration due to gravity and height ie
PE=mgh where PE is the potential energy, m is mass of an object, g is acceleration due to gravity whose value is normally taken as 9.81 and h is height. Since at point R we have the maximum height, the potential energy will be highest at this point.