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100 coplanar forces each equal to 10 N act on a body. Each force makes an angle π/50 with the preceding force. What is the resultant of the forces?

1) 1000 N 2) 500 N 3) 250 N 4) Zero Answer: 4) Zero Total angle=100x (π/50)=2π All the forces will pass through one point and... View Article

A hail has the dimensions 10 m x 12 m x 14 m. A fly starting at one corner ends up at a diagonally opposite corner. What is the magnitude of its displacement?

1) 17 m 2) 26 m 3) 36 m 4) 21 m Answer: 4) 21 m Solution: The magnitude of displacement d = √440 d = 2√110 d = 20. 97 m... View Article

A force of 5 N acts on a particle along a direction making an angle of 60^o with vertical. Its vertical component will be

1) 10N 2) 3N 3) 4N 4) 2.5N Answer: 4) 2.5N Solution: The component of force in the vertical direction = F cosθ = F cos 600 = 5 x (1/2)... View Article

Two trains along the same straight rails moving with constant speed 60 km/hr and 30 km/hr respectively towards each other. If at time t. = 0, the distance between them is 90 km, the time when they collide is

1) 1 hr 2) 2 hr 3) 3 hr 4) 4 hr Answer: 1) 1 hr Solution: Let the two trains be Train A and Train B Speed of train A = 30 km/hr Speed of... View Article

Assertion The minimum number of non-coplanar vectors whose sum can be zero is four. Reason The resultant of two vectors of unequal magnitude can be zero.

Assertion The minimum number of non-coplanar vectors whose sum can be zero is four. Reason The resultant of two vectors of unequal magnitude can... View Article

Assertion: Two vectors are said to be like vectors if they have the same direction but different magnitude. /Reason: Vector quantities do not have a specific direction.

Assertion: Two vectors are said to be like vectors if they have the same direction but different magnitude. Reason: Vector quantities do not... View Article

Assertion: The sum of two vectors can be zero. Reason: The vector cancels each other when they are equal and opposite.

Assertion: The sum of two vectors can be zero. Reason: The vector cancels each other when they are equal and opposite. 1) both Assertion and... View Article

Assertion A physical quantity cannot be called a vector if its magnitude is zeroReason A vector has both, magnitude and direction.

Assertion A physical quantity cannot be called a vector if its magnitude is zero Reason A vector has both, magnitude and direction. 1) If both... View Article

Assertion A null vector is a vector whose magnitude is zero and direction is arbitraryReason A null vector does not exist.

Assertion A null vector is a vector whose magnitude is zero and direction is arbitrary Reason A null vector does not exist. 1) If both... View Article

A motorboat covers a given distance in 6 hr moving downstream on a river.

A motorboat covers a given distance in 6 hr moving downstream on a river. It covers the same distance in 10 hr moving upstream. The time it takes... View Article

A man sitting in a bus travelling in a direction from West to East with a speed of 40 km/hr observes that the raindrops are falling vertically down. To another man standing on ground, the rain will appear

1) To fall vertically down 2) To fall at an angle going from West to East 3) To fall at an angle going from East to West 4) The information... View Article

A thief is running away on a straight road on a jeep moving with a speed of 9 m/s. A police man chases him on a motor cycle moving at a speed of 10 m/s. If the instantaneous separation of jeep from the motor cycle is 100 m, how long will it take for the policemen to catch the thief ?

1) 1 sec 2) 19 sec 3) 90 sec 4) 100 sec Answer: 4) 100 sec Solution: The relative velocity of policeman w.r.t the thief is 10 - 9 = 1... View Article

A river is flowing from East to West at a speed of 5m/min. A man on south bank of river, capable of swimming 10 m/min in still water, wants to swim across to river in the shortest time. He should swim

1) Due North 2) Due North- East 3) Due North-East with double the speed of river 4) None of the above Answer: 1) Due North Solution: To... View Article

A boat takes two hours to travel 8 km and back in still water. If the velocity of water is 4 km/hr, the time taken for going upstream 8 km and coming back is

1) 2 hr 2) 2 hr 40 min 3) 1 hr 20 min 4) Cannot be estimated with the information given Answer: 2) 2 hr 40 min Solution: Speed of boat... View Article

A boat crosses a river with a velocity of 8 km/hr. If the resulting velocity of boat is 10 km/hr, then the velocity of river water is

1) 4 km/hr 2) 6 km/hr 3) 8 km/hr 4) 10 km/hr Answer: 2) 6 km/hr Solution: Boat crosses a river with a velocity, VB = 8 km/hr... View Article