13. Question 3.
A simple pendulum takes 32s to complete 20 oscillations. What is the time period of the pendulum?
Answer:
The time taken to complete one oscillation is known as time period of the pendulum.
Time Period = (Total time taken)/ (Number of Oscillations)
Given: - 20 oscillations taking 32s to complete.
Therefore 1 oscillation will take = (32)/ (20) sec = 1.6 second
Therefore 1.6s is the time period of the pendulum.
14. 1. A fly flaps its wings 90 times in 30
seconds. What is the time period of
flapping of wings?
15. Time period = total time taken/ number
of oscillations
T = 90/ 30
T = 0.33 seconds.
So ,the time period is 0.33 seconds.
16.
17.
18.
19.
20. Uniform Motion
A body is said to be in uniform motion if
it travels in straight line and covers equal
distances in equal interval of time.
21. Non Uniform Motion
A body is said to be in uniform motion
if the speed or direction of the body
does not remains constants.
22.
23. Q3. Determine the time taken when, distance is 7150 km and speed is 780
km/hr.
Given Distance = 7150 km
speed= 780 km/h
Time = Distance /Speed
Q4. If distance travelled by a train is 495 km in 4 hours 30 minutes, what is its
speed?
Given : Distance = 495 Km
Time = 4 h 30 min. 30/60 = 0.5 h
= 4.5 h
Speed = Distance/ Time
24. Q6. The speed of the train is 72 km per hour. Find its speed in metre per second.
72000/3600 =20 m/s
Q7. Express the speed of 60 m per minute in km per hour.
60/1000/1/60 = 60x60/1000
Q8. A man runs at the speed of 10 km/hr. How much time will he take to cover
750 metres?
25. Q9. Aaron ran 500 metre in 100 Seconds. Find the speed in km per hour.
Q10. A cyclist travels at a speed of 20 km/hour. How far will he travels in 50
minutes?
26.
27.
28.
29. Q1.Find speed when, distance is 142 km and time is 2 hours.
Given : Distance = 142 Km
Time = 2h
Speed = distance/Time
Q2. Find out the distance covered when, speed is 960 km/hour
and time is 1 hour 50 minutes.
Given: Speed = 960 Km/h = 960/60 = 16 km/min
Time = 1h 50 min. = 110 min
distance = 16x 110 =1760 km
