Balbharati solutions for Physics [English] 11 Standard Maharashtra State Board chapter 3 - Motion in a Plane [Latest edition]

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An object thrown from a moving bus is on example of _____.

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For a particle having a uniform circular motion, which of the following is constant

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The bob of a conical pendulum undergoes

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For uniform acceleration in rectilinear motion which of the following is not correct?

If three particles A, B and C are having velocities `vec"V"_"A", vec"V"_"B" and vec"V"_"C"` which of the following formula gives the relative velocity of A with respect to B

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Separate the following in groups of scalar and vectors:

velocity, speed, displacement, work done, force, power, energy, acceleration, electric charge, angular velocity

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Define average velocity and instantaneous velocity. When are they same?

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Define free fall.

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If the motion of an object is described by x = f(t), write formulae for instantaneous velocity and acceleration.

Derive equations of motion for a particle moving in a plane and show that the motion can be resolved in two independent motions in mutually perpendicular directions.

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Derive equations of motion graphically for a particle having uniform acceleration, moving along a straight line.

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Derive the formula for the range and maximum height achieved by a projectile thrown from the origin with initial velocity `vec"u"` at an angle θ to the horizontal.

Show that the path of a projectile is a parabola.

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What is a conical pendulum?

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Show that its time period is given by, 2π`sqrt((l cos theta)/("g"))` where l is the length of the string, θ is the angle that the string makes with the vertical, and g is the acceleration due to gravity.

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Define angular velocity.

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Show that the centripetal force on a particle undergoing uniform circular motion is -mrω².

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An aeroplane has a run of 500 m to take off from the runway. It starts from rest and moves with constant acceleration to cover the runway in 30 sec. What is the velocity of the aeroplane at the take-off?

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A car moving along a straight road with a speed of 120 km/hr, is brought to rest by applying brakes. The car covers a distance of 100 m before it stops. Calculate
(i) the average retardation of the car
(ii) time taken by the car to come to rest.

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A car travels at a speed of 50 km/hr for 30 minutes, at 30 km/hr for next 15 minutes and then 70 km/hr for next 45 minutes. What is the average speed of the car?

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A velocity-time graph is shown in the adjoining figure.

Determine:

1. the initial speed of the car
2. the maximum speed attained by the car
3. part of the graph showing zero acceleration
4. part of the graph showing constant retardation
5. distance travelled by car in the first 6 sec.

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A man throws a ball to maximum horizontal distance of 80 m. Calculate the maximum height reached.

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A particle is projected with speed v₀ at angle θ to the horizontal on an inclined surface making an angle Φ (Φ < θ) to the horizontal. Find the range of the projectile along the inclined surface.

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A metro train runs from station A to B to C. It takes 4 minutes in travelling from station A to station B. The train halts at station B for 20 s. Then it starts at station B and reaches station C in next 3 minutes. At the start, the train accelerates for 10 sec to reach a constant speed of 72 km/hr. The train moving at the constant speed is brought to rest in 10 sec. At the next station.
(i) Plot the velocity- time graph for the train travelling from station A to B to C.
(ii) Calculate the distance between the stations A, B and C.

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A train is moving eastward at 10 m/sec. A waiter is walking eastward at 1.2m/sec; and a fly is charging toward the north across the waiter’s tray at 2 m/s. What is the velocity of the fly relative to Earth?

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A car moves in a circle at a constant speed of 50 m/s and completes one revolution in 40 s. Determine the magnitude of the acceleration of the car.

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A particle moves in a circle with a constant speed of 15 m/s. The radius of the circle is 2 m. Determine the centripetal acceleration of the particle.

Solve the following problem.

A projectile is thrown at an angle of 30° to the horizontal. What should be the range of initial velocity (u) so that its range will be between 40m and 50 m? Assume g = 10 m s^-2.