JEE Questions for Physics Motion In A Straight Line Quiz 4

From a tower of height H, a particle is thrown vertically upwards with a speed u. The time taken by the particle, to hit the ground, is n times that taken by it to reach the highest point of its path. The relation among H , u and n is

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2 gH = n2u
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gH = (n – 2)2 u2
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2 gH = nu2 (n – 2)
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gH = (n –u2

A body of mass m moving along a straight line covers half the distance with a speed of 2 ms^-1. The remaining half of the distance is covered in two equal time intervals with a speed of 3 ms^-1 and 5 ms^-1 respectively. The average speed of the particle for the entire journey is

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A train accelerates from rest at a constant rate α for distance x₁ and time t₁, it retards to rest at constant rate β for distance x₂ and time t₂. Which of the relation is correct?

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Physics-Motion in a Straight Line-81426.png

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2 s
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4 s
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8 s
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1 s

A particle is moving with constant acceleration from A to B in a straight line AB. If u and v are the velocities at A and B, respectively then, its velocity at the mid-point C will be

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2)
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A stone dropped from a balloon which is at a height h, reaches the ground after t second. From the same balloon, if two stones are thrown, one upwards and the other downwards, with the same velocity u and they reach the ground after time, t₁ and t₂ second, respectively then

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t = t1 – t2
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2)
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A body of mass m is thrown upwards at an angle θ with the horizontal with velocity v. While rising up the velocity of the mass after t sec will be

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A body is projected vertically upwards. The times corresponding to height h while ascending and while descending are t₁ and t₂, respectively. Then, the velocity of projection is (g is acceleration due to gravity).

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The velocity of particle is v = v₀ + gt + ft².If its position is x = 0 at t = 0, then its displacement after unit time (t =is

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v0 + 2g + 3f
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v0 +g/2 + f/3
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v0 + g + f
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v0 + g/2 + f

The coordinates of a moving particle at any time t are given by x = αt³ and y = βt³ . The speed of the particle at time t is given by

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From the top of tower, a stone is thrown up. It reaches the ground in t₁ sec. A second stone thrown down with the same speed reaches the ground in t₂ sec. A third stone released from rest reaches the ground in t₃ second. Then,

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A police car is travelling in a straight line with a constant speed v. A truck travelling in the same direction with constant velocity 3v/ 2 passes, the police car at t = 0. The police car starts accelerating 10 s after passing the truck, at a constant rate of 3 ms^-2, while truck continues to move at constant speed. If the police car takes 10 s further to catch the truck, find the value of v.

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10 ms-1
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15 ms-1
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20 ms-1
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30 ms-1

A boat travels 50 km due east, then 120 km due north and finally it comes back to the starting point through the shortest distance. The total time of journey is 3 h. What is the average speed (in kmh^-1) over the entire trip?

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Zero
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100
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17
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33.33
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86.7

The acceleration experienced by a moving boat after its engine is cut-off, is given by a = –kv³ , where k is a constant. If v_o is the magnitude of velocity at cut-off, then the magnitude of the velocity at time t after the cut-off is

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Two cars A and B are travelling in the same direction with velocities v₁ and v₂ (v₁ > v₂ ). When the car A is at a distance d behind the car B, the driver of the car A applies the brake producing uniform retardation a. There will be no collision when

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None of these

Given below are four curves describing variation of velocity with time of a particle. Which one of these describe the motion of a particle initially in positive direction with constant negative acceleration?
Physics-Motion in a Straight Line-81471.png

Physics-Motion in a Straight Line-81471.png

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W
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X
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Y
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Z

The displacement-time graphs of two moving particles make angles of 30° and 45° with the X-axis. The ratio of their velocities is
Physics-Motion in a Straight Line-81472.png

Physics-Motion in a Straight Line-81472.png

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1 : √3
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1 : 2
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1 : 1
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√3 : 2

Consider a rubber ball freely falling from a height h = 4.9m onto a horizontal elastic plate. Assume that the duration of collision is negligible and the collision with the plate is totally elastic. Then, the velocity as a function of time will be

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A body is travelling in a straight line with a uniformly increasing speed. Which one of the plot represents the change in distance (s) travelled with time (t)?

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A particle starts from rest at t = 0 and undergoes an acceleration a ( in ms^-1 with time t in second which is as shown. Which one of the following plot represents velocity v in ms^-1 versus time t in second ?
Physics-Motion in a Straight Line-81483.png

Physics-Motion in a Straight Line-81483.png

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A ball is thrown vertically upward. Ignoring the air resistance, which one of the following plot represents the velocity-time graph for the period ball remains in air?

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A body is at rest at x = 0. At t = 0, it starts moving in the positive x-direction with a constant acceleration. At the same instant another body passes through x = 0 moving in the positive x-direction with a constant speed. The position of the first body is given by x₁ (t)after time t and that of the second body by x₂ (t) after the same time interval. Which of the following graphs correctly describe (x₁ – x₂ ) as a function of time t?

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A particle starts from rest at t = 0 and moves in a straight line with an acceleration as shown in figure. The velocity of the particle at t = 3s is
Physics-Motion in a Straight Line-81497.png

Physics-Motion in a Straight Line-81497.png

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2 ms-1
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4 ms-1
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6 ms-1
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8 ms-1
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1 ms-1

An object dropped from rest. Its velocity-time graph is

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A ball is dropped on a floor and bounces back to a height somewhat less than the original height, which of the curves depict its motion, correctly?

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A body starts from rest and moves with uniform acceleration. Which of the following graphs represents its motion

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Velocity-time (v-t ) graph for a moving object is shown in the figure. Total displacement of the object during the time interval when there is non-zero acceleration and
Physics-Motion in a Straight Line-81514.png

Physics-Motion in a Straight Line-81514.png

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60 m
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50 m
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30 m
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40 m

If the figure below represents a parabola, identify the physical quantities representing Y and X for constant acceleration
Physics-Motion in a Straight Line-81516.png