Answer:
The correct answer will be option-B.
Explanation:
A scientific hypothesis is the proposed perdition or idea which is based on the earlier works and knowledge related to the scientific issue. The hypothesis can be tested and proved on the basis of the experiments.
The proved hypothesis can either become law or theory after peer-reviewed by fellow scientists. If the hypothesis still has predictive capabilities help form another hypothesis. Such statements are known as the "theory".
Thus, Option-B is the correct answer.
As the rocket is launched from the ground its height will go on increasing till it stops
So the height of rocket will be maximum when its speed becomes zero
so here we can use energy conservation theory
So it will reach upto height 7.35 m
Answer
given,
mass of the package = 12 kg
slides down distance = 2 m
angle of inclination = 53.0°
coefficient of kinetic friction = 0.4
a) work done on the package by friction is
W_f = -μk R d
= -μk (mg cos 53°)(2.0)
=-(0.4)(8.0 )(9.8)(cos 53°)(2.0)
= -37.75 J
b)
work done on the package by gravity is
W_g = m (g sin 53°) d
= (8.0 )(9.8 )(sin 53°)(2.0 )
=125.23 J
c)
the work done on the package by the normal force is
W_n = 0
d)
the net work done on the package is
W = -37.75 + 125.23 + 0
W = 87.84 J
