Answer:


Explanation:
(a)
Given:
- mass of comet,

- velocity of the comet,

<u>Now, the kinetic energy of the comet can be given by:</u>



(b)
Given:
- energy released by 1 megaton of TNT,

<u>Now the kinetic energy of the comet in terms of energy of 1 megaton TNT:</u>

i.e.

Answer:
The distance is 300 m.
Explanation:
Given that,
Time = 30 s
Speed = 80 m/s
Distance = 1200 m
Speed of smaller plane = 40 m/s
We need to calculate the acceleration
Using equation of motion

Put the value in the equation



We need to calculate the distance
Using equation of motion

Put the value in the equation



Hence, The distance is 300 m.
Answer:
(a) 161.57 N
(b) 0.958 m/s^2
Explanation:
Force applied, F = 220 N
mass of crate, m = 61 kg
μ = 0.27
(a) The magnitude of the frictional force,
f = μ N
where, N is the normal reaction
N = m x g = 61 x 9.81 = 598.41 N
So, the frictional force, f = 0.27 x 598.41
f = 161.57 N
(b) Let a be the acceleration of the crate.
Fnet = F - f = 220 - 161.57
Fnet = 58.43 N
According to newton's second law
Fnet = mass x acceleration
58.43 = 61 x a
a = 0.958 m/s^2
Thus, the acceleration of the crate is 0.958 m/s^2.
Si la velocidad es 3 m/s, y ellos quieren saber la distancia despues 2 segundos, necesita que multiplicar 2 y 3.
La respeusta debiera ser 6m.