dharna is said to be concentration.. it is true
Answer:
1,050 Joules
Explanation:
<u>Step 1:</u> work done in moving the box 30 meters
work done = force X distance
= 25N X 30 = 750 Joules
<u>Step 2: </u>calculate total internal energy
Total internal energy = work done + kinetic energy
= 750 Joules + 300 Joules
= 1,050 Joules = 1.05 KJ
Answer : The kinetic energy depends directly on the mass of a particle.
Explanation :
We know that the kinetic energy of any particle is given by :

Where,
m is the mass of an object.
v is the velocity with which it is moving
Kinetic energy is due to the motion of the particle.
So, the kinetic energy of a particle is directly proportional to its mass.
Hence, the conclusion of the question is if the mass of a particle is increases then its kinetic energy also increase.
Answer:
Option C is the correct answer.
Explanation:
Considering vertical motion of ball:-
Initial velocity, u = 2 m/s
Acceleration , a = 9.81 m/s²
Displacement, s = 40 m
We have equation of motion s= ut + 0.5 at²
Substituting
s= ut + 0.5 at²
40 = 2 x t + 0.5 x 9.81 x t²
4.9t² + 2t - 40 = 0
t = 2.66 s or t = -3.06 s
So, time is 2.66 s.
Option C is the correct answer.