Among the given distancetime graphs, following graph shows the movement of a truck with speed which is not constant:
It is so because in this graph vehicle is not covering equal distances in equal intervals of time.
The steps to be followed are as follows:
(Here, distance may vary in centimeters due to difference in the size of photographs taken. So, follow only the method for finding right answer, which may vary.)
Therefore, distance travelled = 0.5 cm x 100m = 50m
Therefore, speed = 50m / 10s = 5 m/s
Correct option is (iv).
Explanation: Speed is the distance traveled per unit of time. The standard unit of distance is metre (m) and standard unit of time is second (s).
Correct option is (ii).
Explanation: Speed is the distance traveled per unit of time.
Among the vehicles, vehicle A is moving faster than B. It is so because A has travelled greater distance in shorter period of time in comparison to that of vehicle B. Vehicle B has moved lesser distance in greater period of time as depicted in graph.
Average speed of car = (40 km/h + 60 km/h)/2 = 50 km/h
Total distance travelled = speed × total time taken = 50 km/h × (½) h = 25 km/h
Time taken by Salma = 15 min = 15 × 60 s = 900 s
Speed of bicycle = 2 m/s
Let the distance between school and house be x m
Distance travelled = time taken × speed
∴ Distance, x = 900 s × 2 m/s = 1800 m = 1.8 km
$\begin{array}{l}\text{Time periodofasimplependulumisthetimetakentocompleteoneoscillation.}\\ \text{Thetimeperiodisgivenby,}\\ \text{Timeperiod=}\frac{\text{Time taken}}{\text{Number ofoscillations}}=\frac{32\mathrm{s}}{20}=1.6\mathrm{s}\end{array}$
Following statements are not correct:
(ii) Every object moves with a constant speed.
(v) The speed of a train is expressed in m/h.
S.No. 
Straight Line Motion 
Circular Motion 
Oscillatory Motion 
1. 
Motion of a horse pulling a cart on a straight road. 
Motion of a child in a merrygoround. 
Motion of your hands while running. 
2. 
Motion of a train on a straight bridge. 

Motion of a child on a seesaw. 
3. 


Motion of the hammer of an electric bell. 
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