Uniform Motion

Q. The ratio of the numerical values of the average velocity and average speed of a body is always

1. unity
2. unity or less
3. unity or more
4. less than unity

Q. A $150\text{m}$ long train is moving with a uniform velocity of $45\text{km/h}$. The time taken by the train to cross a bridge of length $850\text{m}$ is

1. 56 sec
2. 68 sec
3. 80 sec
4. 92 sec

Q. A car is travelling at a speed of $72\text{km/hr}$. Evaluate the value of speed in $\text{m/s}$.

1. $20\text{m/s}$
2. $10\text{m/s}$
3. $25\text{m/s}$
4. $15\text{m/s}$

Q. A train travels from a city $A$ to city $B$ with a constant speed of $10\text{m/s}$ and returns back to city $A$ in half of the time taken to travel from $A$ to $B$. Find its average speed during the entire journey.

1. $40\text{m/s}$
2. $30\text{m/s}$
3. $15\text{m/s}$
4. $\frac{40}{3}\text{m/s}$

Q. The ratio of the numerical values of the average velocity and average speed of a body is always

Q. A train travels from a city $A$ to city $B$ with a constant speed of $10\text{m/s}$ and returns back to city $A$ in half of the time taken to travel from $A$ to $B$. Find its average speed during the entire journey.

1. $40\text{m/s}$
2. $30\text{m/s}$
3. $15\text{m/s}$
4. $\frac{40}{3}\text{m/s}$

Q.

The positions of an elevator are as shown. Could this be uniform motion

$\begin{array}{ccccc}pos\left(floor\right)& 5& 8& 11& 14\\ time\left(sec\right)& 0& 1& 2& 3\end{array}$

1. Yes

2. No

Q. Two insects Chinki and Minki start to move in from point $A$ in straight line paths in a circle as shown. Chinki travels along $AP$ and Minki along $AM$, on reaching point $M$, Minki insect changes its direction and moves parallel to the line $AP$ and reaches the diametric opposite point $B$. The radius of circle is $5\text{m}$ and line $AP$ makes an angle of ${37}^{\circ }$ with the diameter $AB$. If the speed of Minki insect along $AMB$ is $2\text{m/s}$ constant then how much time (in $\text{sec}$) will Minki take to reach $B$ from $A$.

Q.

At time t = 5 secs, Can you predict which floor the elevator will be on if nobody stops the elevator and there are enough floors in the building.

1. 8 th floor

2. 10th floor

3. 7th floor

4. 6th floor

Q. A truck has to carry a load in the shortest time from one station to another station situated at a distance $L$ from the first. It can start up or slowdown at the same acceleration or deceleration $a$. What maximum velocity must the truck attain to satisfy this condition?

1. $\sqrt{2La}$
2. $\sqrt{5La}$
3. $\sqrt{La}$
4. $\sqrt{3La}$