Advertisements
Advertisements
Question
A bus moving along a straight line at 20 m/s undergoes an acceleration of 4 m/s2. After 2 seconds, its speed will be:
Options
8 m/s
12 m/s
16 m/s
28 m/s
Advertisements
Solution
28 m/s
Acceleration of the moving object is 4 m/s2
Initial velocity is 20 m/s.
Time taken is 2 sec.
By applying 1st equation of motion we get,
v = u + at
= 20 + 2(4)
= 28 m/s
So, the answer is
(d) 28 m/s
APPEARS IN
RELATED QUESTIONS
Joseph jogs from one end A to the other end B of a straight 300 m road in 2 minutes 30 seconds and then turns around and jogs 100 m back to point C in another 1 minute. What are Joseph’s average speeds and velocities in jogging?
- from A to B and
- from A to C?
What name is given to the speed in a specified direction ?
An aircraft travelling at 600 km/h accelerates steadily at 10 km/h per second. Taking the speed of sound as 1100 km/h at the aircraft’s altitude, how long will it take to reach the ‘sound barrier’ ?
A train starting from rest moves with a uniform acceleration of 0.2 m/s2 for 5 minutes. Calculate the speed acquired and the distance travelled in this time.
The tip of seconds’ hand of a dock takes 60 seconds to move once on the circular dial of the clock. If the radius of the dial of the clock be 10.5 cm, calculate the speed of the tip of the seconds’ hand of the clock. `("Given" π= 22/7)`.
A car is moving on a straight road with uniform acceleration. The speed of the car varies with time as follows :
Time (s) : 0 2 4 6 8 10
Speed (m/s) : 4 8 12 16 20 24
Draw the speed-time graph by choosing a convenient scale. From this graph :
(1) Calculate the acceleration of the car.
(2) Calculate the distance travelled by the car in 10 seconds.
Which of the following can sometimes be 'zero' for a moving body?
(i) average velocity
(ii) distance travelled
(iii) average speed
(iv) displacement
Draw the shape of the velocity-time graph for a body moving with (a) Uniform velocity and (b) Uniform acceleration.
Figure shows the displacement of a body at different times .
Calculate the velocity of the body as it moves for time interval :
(i) 0 to 5 s,
(ii) 5 s to 7 s
(iii) 7 s to 9 s.
The velocity-time graph of a moving body is given below in Figure
Total displacement.
