Relative Speed
Everything on SkillVeris tagged Relative Speed — collected across the glossary, study notes, blog, and cheat sheets.
17 resources across 1 library
Interview Questions(17)
How to Solve Time, Speed and Distance Problems
Time, speed and distance problems all reduce to one relation: Distance = Speed × Time, rearranged as Speed = Distance ÷ Time or Time = Distance ÷ Speed, with c…
How to Solve Boats and Streams Problems
Boats and streams problems are solved by adding the stream’s speed to the boat’s speed for downstream travel and subtracting it for upstream travel, then apply…
How to Solve Clock Problems
Clock problems are solved by treating the minute hand and hour hand as two objects moving at fixed angular speeds — 6° per minute and 0.5° per minute respectiv…
How to Solve Trains Crossing Each Other Problems
When two trains cross each other, the relevant speed is their relative speed — the sum of both speeds if moving in opposite directions, or the difference if mo…
How to Solve Relative Speed Problems
Relative speed is the speed at which the gap between two moving bodies changes, calculated as the sum of their speeds when moving toward each other or in oppos…
How to Solve Upstream and Downstream Speed Problems
Downstream speed (with the current) equals boat speed plus stream speed, while upstream speed (against the current) equals boat speed minus stream speed, so bo…
How to Solve Circular Track Race Problems
On a circular track of length L, two runners moving at speeds a and b first meet at L/(a−b) if moving in the same direction, or L/(a+b) if moving in opposite d…
How to Solve Linear Races and Head Start Problems
In a linear race, "A gives B a head start of x meters" means B starts x meters ahead, while "A gives B a start of t seconds" means B starts running t seconds e…
How to Solve Escalator Speed Problems
Escalator problems are relative-speed problems where the escalator itself contributes a constant speed e (in steps or distance per unit time) that adds to a pe…
How to Solve Man vs Train Crossing Problems
When a train crosses a person walking or running, the train covers its own length L relative to that person at their relative speed, so time = L / (relative sp…
How to Calculate the Angle Between Clock Hands
The angle between the hour and minute hands at H hours and M minutes is |30×H − 5.5×M| degrees, taking the smaller of that value and 360 minus that value if it…
How to Solve Clock Coincidence (Hands Overlap) Problems
Clock hands coincide (overlap exactly) 11 times every 12 hours, not 12, because the minute hand must lap the hour hand — cover one extra full circle relative t…
How to Solve Boats and Streams (Relative Speed) Problems
In boats-and-streams problems, effective speed downstream is boat speed plus current speed, and effective speed upstream is boat speed minus current speed, bec…
How to Solve Boats Upstream Time-Ratio Problems
Upstream speed equals boat speed minus current speed, downstream speed equals boat speed plus current speed, and since distance is fixed, the ratio of upstream…
How to Solve Boats Round-Trip Time Problems
A round trip’s total time is the sum of the upstream leg time and the downstream leg time computed separately, total time = d/(b−c) + d/(b+c), which simplifies…
How to Solve Stream Current-Speed Problems
Current speed is found by isolating it algebraically from the two basic relations upstream speed = boat speed − current speed and downstream speed = boat speed…
How to Solve Races and Relative Start-Distance Problems
In race problems, 'A gives B a start of x meters’ means B only needs to cover (track length − x) while A covers the full track length in the same time, so the…