Answer:
a)
, b)
, c) 
Explanation:
a) The change in the gravitational potential energy of the marble-Earth system is:


b) The change in the elastic potential energy of the spring is equal to the change in the gravitational potential energy, then:

c) The spring constant of the gun is:




Explanation:
Newton's second law:
∑F = ma
277 N − 245 N = (25 kg) a
a = 1.28 m/s²
Answer:
Afforestation is the planting or adding of trees in an area where there was never a forest or plantation. This is a method to create a new forest. Reforestation is the replanting of trees in an area where there was once a forest which was destroyed or damaged.
Explanation:
Answer:
1.2 x 10¹¹ kgm²/s
Explanation:
m = mass of the airplane = 39043.01
r = altitude of the airplane = 9.2 km = 9.2 x 1000 m = 9200 m
v = speed of airplane = 335 m/s
L = Angular momentum of airplane
Angular momentum of airplane is given as
L = m v r
Inserting the values
L = (39043.01 ) (335) (9200)
L = (39043.01 ) (3082000)
L = 1.2 x 10¹¹ kgm²/s
Answer:
i. 15.6 m/s
ii. I = 1.44 KNs
Explanation:
The impulse, I, on a body is the product of force applied on it and the time it acts.
i.e I = F x t
Impulse is sometimes expressed as the change in momentum of a body. It is measured in Ns.
i. mass, m, of the player = 92 kg
initial velocity of the player, u = 9.4 m/s
final velocity of the player, v = 6.2 m/s
Since he bounces back on hitting the pole, then the sign of initial and final velocities are of opposite sign.
So that,
change in velocity of the player = final velocity - initial velocity
= 6.2 - (-9.4)
= 6.2 + 9.4
= 15.6 m/s
change in velocity of the player is 15.6 m/s
ii. Impulse, I = m(v - u)
= 92 x 15.6
= 1435.2
Impulse on the player is 1.44 KNs.