Time and Speed

Q.

An artificial satellite is moving in a circular orbit of a radius $42250km$. Calculate its speed if it takes $24$ hours to revolve around the earth.

Q. Match the graphs with the types of motion associated with a body.

1. The body is moving with uniform speed, away from the starting position.
2. The body is moving at a non-uniformly decreasing speed.
3. The body is moving at a non-uniformly increasing speed.
4. The body is moving with uniform speed, towards the starting position.
5. The body is at rest.

1. A - 3, B - 1, C - 5, D - 2, E - 4
2. A - 3, B - 2, C - 1, D - 4, E - 5
3. A - 2, B - 1, C - 5, D - 3, E - 4
4. A - 2, B - 1, C - 5, D - 3, E - 4

Q. How do you determine the average speed of a body in non-uniform motion?​

Q. A boy travels a distance of $150m$ in 1 minute. His speed is :

1. $25m{s}^{-1}$
2. $150m{s}^{-1}$
3. $2.5m{s}^{-1}$
4. $9m{s}^{-1}$

Q. A boy walks a distance $30m$ in $1$ minute and another $30m$ in $1.5$ minute. Describe the type of motion of the boy and find his average speed in $m{s}^{-1}$ .

Q. A train travels 40 km at a uniform speed of $30km{h}^{-1}$. Its average speed after travelling another 40 km is $45km{h}^{-1}$ for the whole journey. Its speed in the second half of the journey is

1. $60km{h}^{-1}$
2. $90km{h}^{-1}$
3. $45km{h}^{-1}$
4. $Noneofthese$

Q.

A man walks $7km$ in $2hours$ and $2km$ in $1hour$ in the same direction. What is mans average speed for the whole journey?

Q.

What is time?

Q. If it takes 8 minutes and 20 seconds for sunlight to reach the earth, find the distance between the Earth and the Sun. The velocity of light is $3\times {10}^{8}m{s}^{-1}$.

1. $15\times {10}^{10}m$
2. $25\times {10}^{10}m$
3. $30\times {10}^{10}m$
4. $5\times {10}^{10}m$

Q. Fill in the blank :
$\text{Total distance travelled}=$ _______$\times \text{total time taken}$.

Q.

Distinguish between speed and velocity.
[3 Marks]

Q. What is motion? Differentiate between slow and fast objects.

Q. A boy travels with a speed of \(10 ~𝑚𝑠^{ −1}\) for 30 minutes. How much distance does he travel?

Q. How long a train will take to travel a distance of
$200km$ with a speed of $60km{h}^{-1}$ .

Q. A vector quantity is a quantity that has both magnitude and direction.

1. True
2. False

Q. Name the device used in a car to measure:[2 marks]
a) how fast you are travelling
b) total distance travelled

Q. An express train takes one hour less than the passenger train to travel 132 km. If the average speed of the express train is 11 km per hr more than the passenger train. What is the average speed of the 2 trains.

Q. A $60m$ long train moving with constant speed on a straight level track passes a pole in $5s$. The time it will take to cross a $540m$ long bridge is:

1. 50

Q. Fill in the blanks :
$Dis\tan cetravelled\left(d\right)=\_\_\_\_\_\_\_\_\_\times time\left(t\right)$

Q.

An artificial satellite is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hours to revolve around the Earth.

1. 2.07 km/s

2. 3.07 km/s

3. 4.21 km/s

4. 1.28 km/s

Q.

An auto travels the first halftime with a uniform speed $u$ and the next halftime with a uniform speed $v$. Find its average speed.

1. 

2. 

3. uv

4. 2uv

Q. Which of the following is the fastest speed among the following?

1. 6 km/min
2. 6 km/s
3. 2 m/s
4. 2000 m/s

Q. When an object doesn't change its position with respect to its surroundings and time, it is said to be at rest.

1. False
2. True

Q.

A particle is moving from point A to point B and covers the entire distance of 10 km in just 2 minutes. What would be the speed at which the particle was traveling?

1. $53.3m{s}^{-1}$

2. $83.3m{s}^{-1}$

3. $90.3m{s}^{-1}$

4. $80.3m{s}^{-1}$

Q. 36 km/h = ___ m/s

Q. A vector quantity is a quantity that has both magnitude and direction.

1. False
2. True

Q.

An auto travels the first half of the total time with a uniform speed u and the other half with a uniform speed v. Find its average speed.

1. 

2. 2uv

3. uv

4. 

Q. has both magnitude and direction.

1. Speed
2. Displacement
3. Distance

Q.

36 km/h = ___ m/s

Q.

36 km/h =

___ m/s