Chapter 1: Nutrition in Plants
Chapter 2: Nutrition in Animals
Chapter 5: Acids, Bases and Salts
Chapter 6: Physical and Chemical Changes
Chapter 7: Weather, Climate and Adaptations of Animals to Climate
Chapter 8: Winds, Storms and Cyclones
Chapter 10: Respiration in Organisms
Chapter 11:Transportation in Animals and Plants
Chapter 12:Reproduction in Plants
Chapter 14: Electric Current and Its Effects
Chapter 16:Water: A Precious Resource
Motion and Timers
(i) Motion of your hands while running.
(ii) Motion of a horse pulling a cart on a straight road.
(iii) Motion of a child in a merry-go-round.
(iv) Motion of a child on a see-saw.
(v) Motion of the hammer of an electric bell.
(vi) Motion of a train on a straight bridge.
i) oscillatory
ii) Motion along a straight line
iii) Circular motion
iv) Oscillatory motion
v) Oscillatory motion
vi) Motion along a straight line.
(i) The basic unit of time is second.
(ii) Every object moves with a constant speed.
(iii) Distances between two cities are measured in kilometres.
(iv) The time period of a given pendulum is constant.
(v) The speed of a train is expressed in m/h.
Incorrect statements are:
(ii) Every object moves with a constant speed.
(iv) The time period of a given pendulum is constant.
(v) The speed of a train is expressed in m/h.
Number of oscillations = 20
time = 32 s
Time period =Distance s = 240 km
Total time = 4 hr
Speed =Initial reading = 57321.0
Final reading = 57336.0
time taken by car = 20 min
Distance covered by the car = Final reading – Initial reading
= 57336.0 – 57321.0 = 15 km
Speed =Time taken = 15 mins= 15 x 60 = 900 s
Speed of bicycle= 2m/s
Speed =Distance = speed x time taken
= 2 x 900 = 1800 m
1m =(i) A car moving with a constant speed.
(ii) A car parked on a side road.
(i) Speed = Distance × Time
(ii) Speed = Distance/Time
(iii) Speed = Time/Distance
(iv) Speed = 1/Distance x Time
(ii) Speed = Distance/Time
(i) km/min
(ii) m/min
(iii) km/h
(iv) m/s
(iv) m/s
(i) 100 km (ii) 25 km (iii) 15 km (iv) 10 km
Speed = 40 km/h
Time taken = 15 min = 15/60 = 0.25 h
Speed =Distance covered (when speed is 40km/h) = speed x time
= 40 x 0.25 = 10 km
When the speed of the Car is 60 km/ h
Speed =Distance covered (when speed is 60km/h) = speed x time
= 60 x 0.25= 15 km
Total distance covered by the car =Distance covered (when speed is 40km/h) + Distance covered (when speed is 60km/h)
= 10 + 15 = 25 km
So (ii) 25 km is correct
Vehicle A is moving faster than vehicle B because large distance coverd by A in less time than B .
( iii)
Chapter 1: Nutrition in Plants
Chapter 2: Nutrition in Animals
Chapter 5: Acids, Bases and Salts
Chapter 6: Physical and Chemical Changes
Chapter 7: Weather, Climate and Adaptations of Animals to Climate
Chapter 8: Winds, Storms and Cyclones
Chapter 10: Respiration in Organisms
Chapter 11:Transportation in Animals and Plants
Chapter 12:Reproduction in Plants
Chapter 14: Electric Current and Its Effects
Chapter 16:Water: A Precious Resource