A farmer moves along the boundary of a square field of side 10 m in 40 s. What will be the magnitude of displacement of the farmer at the end of 2 minutes 20 seconds from his initial position?

Question:

Answer:

Total distance traveled by farmer in

40s = 4×10 =40m

Total time taken =2 min×20 sec =140 sec

Total number of rounds =140/40 =3.5

If the farmer starts from A, then after 3.5 rounds, he reaches to point ′C′.

Therefore, displacement =AC.

Now, ABCD is a square, then △AB is a right-angled △.

Using Pythagoras theorem,

AC2=AB2+BC2⇒AC=√102+102=√200=10√2

AC= 10×1.414=14.14m

Hence, displacement =14.14m

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An artificial stellite is moving in a circular obrit of radius 42250 km. Calculate it's speed if it takes 24 hour to revolve around the earth.

State which of the following situations are possible and give an example for each of these. (a)An object with a constant acceleration but with zero velocity. (b) An object moving in a certain direction with an acceleration in the perpendicular direction.

The speed time graph for a car is shown in the figure. (a) Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period. (b) Which part of the graph represents uniform motion of the car?

A ball is gently dropped from a height of 20m. If it's velocity increases. Uniformly at the rate of 10 m/s2 with what velocity will it strike the ground? After what time will it strike the ground?

Figure shows the distance-time graph of three objects A, B and C. Study the graph and answer the following questions.

A motorboat starting from rest on a lake accelerates in a straight line at a constant rate of 3.0 m/s–2 for 8.0s. How far does the boat travel during this time?

Abdul, while driving to school, computes the average speed for his trip to be 20 km h–1. On his return trip along the same route, there is less traffic and the average speed is 30 km h–1. What is the average speed for Abdule's trip?

Joseph jogs from one end A to the other end B of a straight 300 m road in 2 minutes 30 seconds and then turns around and jogs 100 m back to point C in another 1 minute what are joseph's average speed and velocities in jogging (a) from A to B and (b) from A to C.

A stone is thrown in a vertically upward direction with a velocity of 5 ms–1. If the acceleration of the stone during its motion is 10 ms–2 in the downward direction, what will be the height attained by the stone and how much time will it take to reach there?

A racing car has a uniform acceleration of 4 m s–2. What distance will it cover in 10 s after start?

A train is moving with a speed of 90 km/h. When brakes are applied, a retardation of 0.5 m/s2 is produced. How much distance will the train cover before it stops and how long will it take?

What is the quantity which is measured by the area occupied below the velocitytime graph?

What can you say about the motion of an object if its speed time graph is a straight line parallel to the time axis?

What can you say about the motion of an object whose distance-time graph is a straight line parallel to the time axis?

What is the nature of the distance-time graphs for uniform and non-uniform motion of an object?

A train starting from a railway station and moving with uniform acceleration attains a speed of 40 km h–1 in 10 minutes. Find its acceleration.

A bus decreases its speed from 80 km h–1 to 60 km h–1 in 5 s. Find the acceleration of the bus.

When will you say a body is in (i) uniform acceleration? (ii) non-uniform acceleration?

During an experiment, a signal from a spaceship reached the ground station in five minutes. What was the distance of the spaceship from the ground station? The signal travels at the speed of light, that is, 3 × 108 ms–1

What does the path of an object look like when it is in uniform motion?

What does the odometer of an automobile measure?

Under what condition(s) is the magnitude of average velocity of an object equal to its average speed?

Distinguish between speed and velocity.

Which of the following is true for displacement? (a) It cannot be zero. (b) Its magnitude is greater than the distance travelled by the object.

An object has moved through a distance. Can it have zero displacement? If yes, support your answer with an example.

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