Saved Bookmarks
| 1. |
1: A hammer of mass 1 kg falls freely from a height of 2m. Calculate.. (a) the velocity with which it hits the ground and (b) the kinetic energy of the hammer just before it touches the ground.2: A bullet of mass 20 g moving with a velocity of 20 m/s is brought to rest by a wooden plank. Calculate the work done on the bullet before it comes to rest.❌ PLEASE don't SpaM❌ |
|
Answer» tion:1. Velocity of HAMMER, v = 6.26 m/s2. KINETIC energy, E = 19.59 JExplanation:It is given that,Mass of the hammer, m = 1 kgHeight, h = 2 m(1) Let v is the velocity of hammer. It can be calculated using conservation of energy as :v=\sqrt{2gh}v= 2gh v=\sqrt{2\times 9.8\times 2}v= 2×9.8×2 v = 6.26 m/s(2) Let E is the kinetic energy of the hammer just before it touches the GROUND. It is given by :E=\dfrac{1}{2}mv^2E= 21 mv 2 E=\dfrac{1}{2}\times 1\times (6.26)^2E= 21 ×1×(6.26) 2 E = 19.59 J |
|