Question
If a boat travels 18 km more in downstream than in
upstream in 3 hours and if the speed of the Boat in still water is 20 kmph. Find the distance travelled by boat in downstream in 4 hours?Solution
Difference in travelling distance in downstream and upstream in 1 hour is 6 km Let the speed of upstream be x km/hr Speed of downstream = x + 6 km/hr speed of the Boat in still water = 20 km/hr 1/2 x (x + x + 6) = 20 2x + 6 = 40 x = 17 km/hr Speed of downstream = 17 + 6 = 23 km/hr Distance travelled in 4 hours = 23 x 4 = 92 km
Which law describes the relationship between the force applied to a spring and its extension or compression?
What is the value of 1 horsepower in watts?
Which of the following is a characteristic of a conductor?
The speed of a fast moving electron, having total energy of 2 MeV, is nearly:
A ray of light passing through an equilateral triangular glass prism from air undergoes minimum deviation when angle of incidence is 75% of the angle o...
A porter lifts luggage of 20 kg from the ground and puts it on his head 2 m above the ground. Calculate the work done by him on the luggage (take g = 10...
A silicon sample is doped such that the number of holes far exceeds the number of electrons. Which of the following is true about its conductivity?
An electric heater draws a current of 6 A from a 220 V supply. What is the power consumed?
A particle is projected such that its velocity vector sweeps equal angles with horizontal at equal time intervals. The motion is best described as:
A Zener diode differs from a regular diode in that:
Relevant for Exams:
