Concept explainers
(a)
The distance travel by the Desmond in
(a)
Answer to Problem 2PQ
The distance travel by the Desmond in
Explanation of Solution
The speed of Desmond’s train is towards east.
Write the formula for distance traveled in time
Here,
Find the relative velocity of Desmond with respect to farmer.
Here,
Substitute
Conclusion:
Substitute
Therefore, distance travel by the Desmond in
(b)
The distance travel by the Lilani in
(b)
Answer to Problem 2PQ
The distance travel by the Lilani in
Explanation of Solution
Lilani will travel with speed of train with respect to the farmer because farmer is stationary.
Find the velocity of Desmond with respect to farmer.
Here,
Substitute
Conclusion:
Substitute
Therefore, distance travel by the Lilani in
(c)
The distance travelled by Desmond with respect to Lilani.
(c)
Answer to Problem 2PQ
The distance travel by the Desmond with respect to Lilani in
Explanation of Solution
Calculate the relative velocity of Desmond with respect to Lilani.
Here,
Rewrite the above relation for
Write the formula for distance traveled in time
Conclusion:
Substitute
The negative sign indicates that Desmond lags behind
Therefore, distance travel by the Desmond with respect to Lilani in
(d)
The distance travelled by Lilani with respect to Desmond.
(d)
Answer to Problem 2PQ
The distance travel by Lilani with respect to Desmond in
Explanation of Solution
Calculate the relative velocity of Lilani with respect to Desmond.
Here,
Write the formula for distance traveled in
Conclusion:
Substitute
The positive value indicates that Lilani goes
Therefore, distance travel by Lilani with respect to Desmond in
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Chapter 39 Solutions
Physics for Scientists and Engineers: Foundations and Connections
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