Question

A car moves first for 0.1 hour with a velocity of 20 km/h, then for 0.4 hour with a velocity of 60 km/h and in the last for 0.2 hour with a velocity of 20 km/h. Draw time velocity graph for the car and use it to find:
(i) How much distance the car moves in the first time interval.
(ii) How much distance the car most in the whole journey.
(iii) How much time the card take in first 14 km. Indicate that area in your graph which indicates the journey of first 40 km.

Answer 1

Explanation:

We know that

Velocity(V) = Displacement(S) / time(t) taken

1) Time taken = 0.1 hr

Velocity = 20km/hr

so, Distace = V × t

= 20× 0.1 km

= 2 km

2) Distance travelled by car in whole journey.

Average velocity = (V1+ V2 +V3) / 3

=(20+60+20)/3 km/hr

= 100/3 km/hr

Total time taken =( .1)+ (.4) +(.2) hr

= .7 hr

So, Total distance travel = Average velocity×Total time taken

=100/3 × .7 km

= 70/3 km

= 23.33 km

3) Time taken by car in first 14 km

=Distance / Average velocity

= 14 / (100/3)

= 14×3 /100

= 42/100

= .42 hr

Answer 2

Explanation:

Photosynthesis is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.