Question

PLEASE ANSWER MY QUESTION AS FAST AS POSSIBLE......THE CORRECT ANSWER WILL BE MARKED AS BRAINLIEST.....

Answer 1

Hey Mate !

Here is your solution :

3.

= Distance travelled ∝ time

Let the distance is s and time it t.

= s ∝ t

•°• s = kt ( k is constant term )

Now,

=> speed = Distance travelled ÷ time

=> Speed = s / t ----------- ( 1 )

Let's double the time,

To satisfy the above equation, we have to also double the distance.

•°• 2s = 2kt

Now,

=> speed = Distance travelled ÷ time

=> Speed = 2s / 2t

•°• Speed = s / t --------( 2 )

From ( 1 ) and ( 2 ) , we get that speed is constant with respect to time.

C. Constant Speed

4.

Given,

Speed = 36 km/h

Time = 15 mins = ( 1/4 ) h

Using formula :

=> Speed = Distance travelled ÷ Time

=> 36 km/h = Distance travelled ÷ ( 1/4 )h

=> Distance travelled = ( 36 km/h ) × (1/4)h

•°• Distance travelled = 9 km

Ans : 9 km

5.

Given,

Initial Velocity ( u ) = 36 km/h = 10 m/s

Final velocity ( v ) = 108 km/h = 30 m/s

Time ( t ) = 10 s

Acceleration ( a ) = ?

The options are given to find the acceleration in m/s².

So, first of all we need to convert velocities in m/s.

To convert km/h in m/s , we multiply it by ( 5/18 ).

✓ Initial velocity = 36 km/h

= 36 × ( 5/18 ) m/s

✓ = 10 m/s

✓ Final velocity = 108 km/h

= 108 × ( 5/18 ) m/s

✓ = 30 m/s


Now,

=> Acceleration ( a ) = ( v - u ) ÷ t

=> a = [ ( 30 m/s ) - ( 10 m/s ) ] ÷ 10 s

=> a = ( 20 m/s ) ÷ 10 s

=> a = ( 20 m / 10 s² )

=> a = 2 m/s²


Ans : 2 m/s²

6.

Given,

Initial velocity ( u ) = 20 m/s

Acceleration ( a ) = 4 m/s²

Time ( t ) = 2 s

Final velocity ( v ) = ?

Using 1st equation of Motion,

=> v = u + at

=> v = ( 20 m/s ) + ( 4 m/s² ) × 2 s

=> v = ( 20 m/s ) + ( 8m/s )

=> v = 28 m/s

Ans : 28 m/s

✓ If you have any doubt regarding to solution feel free to ask in comment box.

✓ Proud to be an Indian !

==============================

Hope it helps ! ^_^