Q1) In a 100m track event the time taken by four runners is 10sec,10.2sec,10.4sec and 10.6sec.Find the ratio of their speed?

Q2)In a 4x100m relay race total length is 200m and time taken by one particular group is 50.2s.What is the average velocity and average speed of that group?

Q3)In a long jump event,the total path covered by an athlete is 10.6m.Is it distance or displacement?Why?Give reason for your answer?

2
In question no2 is the path a circle of a straight line

Answers

2015-06-13T17:45:01+05:30
Speed of 1st runner- distance/time 100/10 =10m/sec Speed of 2nd runner=distance/time = 100/10.2 =100×2/10=20m/sec Speed of 3rd runner=distance/time =100/10.4=100×4/10=40m/sec Speed of 4th runner =distance/time =100/10.6=100×6/10=60m/sec Now ratio 10/20/40/60 =10×1/20×1/40×1/60= 1:4800 ANSWER OF QUESTION 3 It is both distance as well as displacement Because in a game of long jump it is a strqight line to be covered So in a straight line distance and displacement is same. Therefore the given magnitude is distance as well as its displacement
0
2015-06-13T20:30:20+05:30
First answer : distance (s)=100m
time
T₁=10
T₂=10.2
T₃=10.4
T₄=10.6
by v=
we get
V₁=
V₁=10m/s

V₂=
V₂=9.8m/s

V₃=
V₃=9.61 m/s

V₄=
V₄=9.43 m/s

V₁:V₂:V₃:V₄ = 10 : 9.8 : 9.61 : 9.43

'






3rd answer 

so,if the athelete goes straight then its both distance and displacement.
if he goes zigzag then he covered both distance and displacement but in this case displacement is shorter than distance

0