Answer:
Convection is the transfer of thermal energy from one place to another by the movement of gas or liquid particles. How does this happen? As a gas or liquid is heated, the substance expands. This is because the particles in liquids and gases gain kinetic energy when they are heated and start to move faster.
Answer:

Explanation:
As we know that the satellite revolves around the planet then the centripetal force for the satellite is due to gravitational attraction force of the planet
So here we will have

here we have


here we have

now we can find time period as




Now the density is given as



Answer:
Thrust due to fuel consumption must overcome gravitational force from the Earth to send the rocket up into space.
Explanation:
From the concept of Escape Velocity, derived from Newton's Law of Gravitation, definition of Work, Work-Energy Theorem and Principle of Energy Conservation, which is the minimum speed such that rocket can overcome gravitational forces exerted by the Earth, and according to the Tsiolkovski's Rocket Equation, which states that thrust done by the rocket is equal to the change in linear momentum of the rocket itself, we conclude that thrust due to fuel consumption must overcome gravitational force from the Earth to send the rocket up into space.
Answer:

Explanation:
Given the mass as M, the rotational inertia of the mower is;

-The roller doesn't slip while rolling;


Answer:
acceleration of the car is 3 m\s^2
Explanation:
from rest means the initial velocity (vi) is zero
time = 5s
final velocity (vf) = 15m\s
a = vf - vi \ t
a = (15-0) \ 5
a= 3 m\s^2
which means that the car is speeding up 3 meters every second