Posted on : March 28, 2020 By Team thecourseshub 1. If h=R then angle of projection is45ᶿ76ᶿ60ᶿ90ᶿ2. The speed of projectile at its highest point if it is projected with initial velocity v_{i} and at an angle 45 with the horizontal.vi/2vi/4vi/(2)1/2vi/33. Swimming is possible on account of 1st law of motion 2nd law of motion 3rd law of motion Newton’s law of gravitation4. What is the angle of projection for which the range and maximum height become equal? tan^-1(1/4) tan^-1(4) tan^-1(1/2) tan^-1(2)5. The ratio of range to height at 45ᶿ is1:41:24:12:16. A stone is thrown vertically upwards with the velocity of 30ms^{-1}. If the acceleration due to gravity is 10ms^{-2}. What is the distance traveled by the particle during the first second of its motion. Take g=10ms^{-2}30 m25 m20 mNone of these7. Motorcycle safety helmet extends the time of collision hence decreasing theChange of collisionForce actingVelocityImpulse8. Velocity and acceleration are in the same direction when Velocity of car is increasing in the straight road Velocity of car is decreasing in the straight road Car is turning round a corner None of these9. The momentum of particle is numerically equal kinetic energies. What is the velocity of the particle?9ms^-13 ms^-12 ms^-11 ms^-110. Two masses of 1 g and 4 g are moving with equal kinetic energies .The ratio of the magnitudes of their linear momenta is4:12:11:21:1611. The ratio of height and range of projectile when projected at an angle θ is4:tan θtan θ:44tan θtan θ+412. A force of 100N acts in a body for 4sec, what will be the change in momentum25 Ns250 Ns400 Ns8000 Ns13. A bomb of mass 12kg, initially at rest, explodes into two pieces of masses 4kg and 9 kg. Speed of the 8kg mass is 6ms^{-1} the kinetic energy of the 4kb mass is32 J48 J114 J288 J14. At maximum height on trajectory which of projectile becomes zeroAccelerationVelocityVertical velocityHorizontal velocity15. A body is moving with uniform velocity. ItsSpeed changesAcceleration changesDirection of motion changesDisplacement from origin changes16. Time rate of change of momentum is equal toForceImpulseVelocityBoth a and b17. The distance covered by the body in time t staring from rest isat^2/2vta^2t/2at^218. A ball is projected at 45ᶿ and its horizontal range is 10m. Velocity of projection is7(3)^1/3ms^-115 ms^-19.6 ms^-114 ms^-119. Momentum depends upon Force act on the body Mass of the body Velocity of the body Both mass and velocity of the body20. If the momentum of the body changes from 100Ns in 10s then the unbalance external force responsible to change the momentum is 5N 2.5N 2N 10N21. Two bodies are projected at angle θ and (90ᶿ-θ) with the horizontal at the same speed. The ratio of their maximum heights is1:11:tanθtanθ:1tan^2:122. A body starting from rest covers a distance of 0.45lm and acquires a velocity pf 300km/hr. Its acceleration will be (ms^{-2})0.0940.77.710.1423. If the velocity time graph is a straight line parallel to time axis then body is Moving with zero acceleration Moving with constant velocity Covering equal displacement is equal intervals of time All of these24. When car takes turn around a curve road, the passenger feel a force acting on them in direction away from the center of the curve. It is due toCentripetal forceGravitational forceTheir inertiaCentrifugal force25. The range of a projectile when launched at an angle of 15ᶿ with the horizontal is 1.5 m. its range, when launched at 45ᶿ with the same speed is3 m1.5 m6 km0.75 km26. The angle of projection, at which the range of projectile would become half of its45ͦᶿ30ᶿ15ᶿ60ᶿ27. Which law of motion is also called Law of inertia?1st law2nd law3rd lawAll 1st , 2nd and 3rd law28. Which one of the following is not an example of projectile motionA gas filled balloonBullet fired from gunA football kickedA bese ball shot29. To a person going east in a car with the velocity of 10ms^{-1}, a train appears to move towards north with the velocity of 10(3)^{1/2}ms^{-1} .The actual velocity of the train is10ms^-1 northeast10ms^-1 northwest20ms^-1 northeast20ms^-1 northwest30. When the average velocity of the moving body is equal to its instantaneous velocity then itUniform velocityVariable velocityUniform accelerationVariable acceleration31. If air considered, then the maximum height achieved by the projectileDecreaseIncreaseRemain sameNone32. The ratio of distance to magnitude of displacement along a semi-circle of radius r is2πππ/23π33. An athlete completes one round of a circular track of Radius R in 40s. What will be displacement at the end of two minutes02RR3πR34. The weight of objects in a rocket when its engine are operatingIs constantIs decreasingIs increasingIs zero35. When the mass and speed of a body are doubled K.E of body wouldBecomes 4 timesBecomes 8 timesBecomes 6 timesUnchanged36. At the highest point on the trajectory of a projectile, itsPotential energy is minimumKinetic energy is maximumTotal energy is maximumKinetic energy is minimum37. When the fighter plane chasing another plane opens fire, its speedIncreaseRemain sameDecreaseFirst decrease then increase38. If two forces inclined at 120ͦᶿ with each other are acting on a body of mass m, then the acceleration produced in the body will beF/m3F/m2F/mF2/m39. Speedometer of an automobile measureAverage velocityInstantaneous velocityAccelerationInstantaneous speedTime is Up!