What is full form of CFLs
compact fluorescent lamps (CFLs)
Science
What is an electromagnet?
A current carrying coil of an insulated wire wrapped around a piece of iron is called an electromagnet. Electromagnets are used in many devices.
What is battery?
h a combination of two or more cells is called a battery.
A car moves with a speed of 40 km/h for 15 minutes and then with a
speed of 60 km/h for the next 15 minutes. The total distance covered by
the car is:
(i) 100 km (ii) 25 km
(iii) 15 km (iv) 10 km
case i , speed = 40 km/h ,time = 15 min= 0.25 hour , distance = speed x time = 40 x 0.25 = 10 km case ii , , speed = 60 km/h ,time = 15 min= 0.25 hour , distance = speed x time = 60 x 0.25 = 15 km total distance …
Salma takes 15 minutes from her house to reach her school on a
bicycle. If the bicycle has a speed of 2 m/s, calculate the distance
between her house and the school.
Time = 15 min = 15*60 sec = 900 sec Seped = 2 m/s Distance = speed * time = 2 m/s * 900 sec = 1800 m
The distance between two stations is 240 km. A train takes 4 hours to
cover this distance. Calculate the speed of the train.
Distance (d) = 240 km = 240 * 1000 = 240000 m Time = 4 hours = 4* 3600 SEC = 14400 SEC SPEED = DISTANCE/ TIME = 240 KM/ 4 HOURS = 60 KM/HR OR , SPEED= D/T = 240000 m / 14400 s = 16.67 m/s
A simple pendulum takes 32 s to complete 20 oscillations. What is the
time period of the pendulum?
Time= 32 sec , No of Oscillation = 20 oscillation Time period = ? Time period = No of oscillation /time = 20/32 = 0.625 sec
Speed and its basic unit
The speed of an object is the distance travelled divided by the time taken to cover that distance Its basic or, S.I unit is metre per second (m/s).