Exercises: Speed

A cyclist covers $100\ \text{m}$ in $20\ \text{s}$. At what speed did they travel? Express the result in $\text{m/s}$.

A commuter train covers $240\ \text{km}$ in $2\ \text{h}$. What was its speed? Express it in $\text{km/h}$.

Who moves faster: a runner covering $100\ \text{m}$ in $12\ \text{s}$ or a swimmer covering $50\ \text{m}$ in $25\ \text{s}$? Calculate the speed of each and compare them.

A car covers $150\ \text{km}$ in $1.5\ \text{h}$. What speed did it travel at, in $\text{km/h}$?

A snail moves forward $1.2\ \text{m}$ in $10\ \text{min}$. What is its speed in $\text{m/min}$?

Complete the sentence with the missing words: "Speed indicates the $\dots$ covered by a body in each $\dots$ of time." Then give a numerical example.

A commercial airliner covers $900\ \text{km}$ in $1.5\ \text{h}$. What is its speed in $\text{km/h}$?

A car travels at $90\ \text{km/h}$. Express its speed in $\text{m/s}$.

An athlete runs at $15\ \text{m/s}$. Express their speed in $\text{km/h}$.

A velociraptor runs at $10\ \text{m/s}$. What distance does it cover in $45\ \text{s}$ if it maintains that speed?

How long does a truck take to cover $200\ \text{km}$ if it travels at a constant speed of $80\ \text{km/h}$? Express the result in hours, and in hours and minutes.

A cyclist covers $30\ \text{km}$ in the first hour of a ride and another $30\ \text{km}$ in the following half hour. Calculate their average speed over the whole trip, in $\text{km/h}$.

An intercity bus covers $180\ \text{km}$ in $2\ \text{h}\ 15\ \text{min}$. What was its average speed in $\text{km/h}$?

How many meters does an electric scooter traveling at $18\ \text{km/h}$ cover in one minute?

Sound travels through the air at about $340\ \text{m/s}$. You see lightning strike and hear the thunder $5\ \text{s}$ later, as shown in the figure.

How far away from you did the lightning strike?

A car covers $100\ \text{km}$ at $100\ \text{km/h}$ and another $100\ \text{km}$ at $50\ \text{km/h}$, as shown in the figure.

1. a) Calculate the time it takes for each section.
2. b) Calculate the average speed for the whole trip.
3. c) Explain why the average speed is not $75\ \text{km/h}$, the mean of the two speeds.

Order the following speeds from fastest to slowest, first expressing all of them in $\text{km/h}$:

1. a) $25\ \text{m/s}$
2. b) $100\ \text{km/h}$
3. c) $1\ \text{km/min}$

During a storm you hear thunder $3\ \text{s}$ after seeing the lightning strike. Sound travels through the air at $340\ \text{m/s}$.

1. a) How far away from you did the lightning strike occur?
2. b) If during the next strike the thunder takes $10\ \text{s}$, is the storm approaching or moving away? Justify your answer with a calculation.

A cyclist rides down a $12\ \text{km}$ mountain pass in $15\ \text{min}$.

1. a) What is their average speed in $\text{km/h}$?
2. b) And in $\text{m/s}$?
3. c) If they descended at that same speed, how long would it take them to ride down a $20\ \text{km}$ mountain pass?

In $2009$ Usain Bolt ran the $100\ \text{m}$ in $9.58\ \text{s}$, setting a world record.

1. a) What was his average speed in $\text{m/s}$?
2. b) Express it in $\text{km/h}$.
3. c) A cheetah can run at $30\ \text{m/s}$. How long would a cheetah take to cover $100\ \text{m}$ at that speed?

To get from your home to the neighboring town it takes $3\ \text{h}$ by bicycle traveling at $50\ \text{km/h}$... impossible, right? Read carefully: a car takes $3\ \text{h}$ to cover that distance at $50\ \text{km/h}$.

1. a) What is the distance between the two towns?
2. b) At what speed would the car have to travel to make the same trip in $2\ \text{h}$?

A family takes a $300\ \text{km}$ road trip by car. They want to take $4\ \text{h}$ in total. After $2\ \text{h}$ of driving, they have covered $150\ \text{km}$.

1. a) What is their average speed so far?
2. b) What average speed must they maintain over the remaining distance to arrive on time?

Two towns are $30\ \text{km}$ apart. A cyclist leaves the first town at $20\ \text{km/h}$ and, at the same time, another leaves the second town at $10\ \text{km/h}$, each heading toward the other's town, as shown in the figure.

1. a) How many kilometers closer to each other do they get every hour?
2. b) How long does it take for them to meet?
3. c) At what distance from the first town do they meet?