2. What is the difference between scalar and vector quantity?

Scalar quantity is a physical quantity that has only magnitude while vector quantity requires both magnitude and direction.

Scalar quantity: Mass, temperature, Distance, energy, speed etc. 

Vector quantity: Force, velocity, acceleration, momentum etc.

3. What is displacement, Can displacement be zero?

Displacement is the shortest distance travelled by an object in a specific direction, from its initial to its final position. Yes, displacement can be zero when the initial and final positions are the same.

5. A cyclist is moving with a velocity of 5 m/s. He accelerates at a rate of 2 m/s² for 10 seconds. Calculate the distance covered by him.

Initial velocity (u) = 5 m/s

Acceleration (a) = 2 m/s²

Time (t) = 10 s

We know that, s = ut + (1/2)at²

s = 5*10 + (1/2)2(10)²

s = 100 m
Therefore, the cyclist covers a distance of 100 m.

6. What is the difference between uniform and non-uniform motion?

Uniform motion is when an object travels equal distances in equal intervals of time, i.e. Velocity is constant. Non-uniform motion is when an object travels unequal distances in equal intervals of time, i.e. Velocity is not constant.

10. How can we convert km/hr to m/s and what will be the speed of the body in m/s and km/hr if it travels 40 kms in 5 hrs?

To convert km/hr to m/s, multiply the value by 5/18.

Distance(s) = 40 km

Time(t)  = 5 hrs.

Speed(in km/hr) = Total distance/Total time = 40/5 = 8 km/hr

Speed (in m/s) = (8 × 5/18)= 40/18 = 2.22 m/s

11. What is velocity?

Velocity is a vector quantity that describes the rate at which an object changes its position. It is defined as the displacement of an object per unit time and includes both magnitude (speed) and direction. The SI unit for velocity is meters per second (m/s).

14. A car starts from rest and reaches a velocity of 20 m/s in 5 seconds. Calculate its acceleration.

Initial velocity (u) = 0 m/s

Final velocity (v) = 20 m/s

Time (t) = 5 s

Acceleration (a) = ?

We know that, a = (v-u)/t

a = (20-0)/5

a = 4 m/s²

Therefore, the acceleration of the car is 4 m/s².

17. What is the first equation of motion?

The first equation of motion is v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time taken. This equation can be used to calculate the final velocity of an object when we know the initial velocity, acceleration, and time.

18. What is the second equation of motion?

The second equation of motion is s = ut + 1/2 at², where s is the distance traveled, u is the initial velocity, a is the acceleration, and t is the time taken. This equation can be used to calculate the distance traveled by an object when we know the initial velocity, acceleration, and time.

19. What is the third equation of motion?

The third equation of motion is v² = u² + 2as, where v is the final velocity, u is the initial velocity, a is the acceleration, and s is the distance traveled. This equation can be used to calculate the final velocity of an object when we know the initial velocity, acceleration, and distance traveled.