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A particle is acted upon by a constant force, the magnitude of which is always perpendicular to the velocity of particle. The motion of particle takes place in same plane. From the above statement it implies

(A) Particle is moving in a circular path

(B) Magnitude of its acceleration is constant

(C) Its velocity is uniform

Read the passage carefully and answer Q.

A dancer demonstrating dance steps along a straight line. The position time graph is given below.

The average velocity of the dancer during time interval between t = 4.5 s to t = 9 s is

(A) 1 ms^-1

(B) -1.33 ms^-1

(C) 2.75 ms^-1

The given shape can be made by using two of which shapes ?

(a)
(b)
(c)
(d)

A body goes from point X to point Y with a speed of 10 m s^-1. It comes back to X with a speed of 20 m s^-1. The average speed of the body during the journey is ______.
(a) 15 m s^-1
(b) 16.6 m s^-1
(c) 13.3 m s^-1
(d) 30 m s^-1

(A) 2, 9, 1, 6

(B) 1, 6, 3, 4

(C) 4, 18, 2, 12

(D) 2, 17, 1, 7

Which of the following is an incorrect match?

(A) Alexander Fleming - Penicillin

(B) Louis Pasteur - Fermentation

(C) Edward Jenner - Vaccination

(A) (a) & (b)

(B) (b) & (c)

(C) (a) & (c)

(D) (a), (b) & (c)

In terrestrial plants, roots normally play a very important role in the absorption of nutrients and water from the soil. However, in aquatic plants, roots are much reduced in size. Some of these plants have narrow and thin ribbon-like leaves. These can bend in the flowing water. In some submerged plants, leaves are often highly divided.
Why are their leaves ribbon-shaped or divided ?
(a) The water can easily pass through these leaves without damaging them.
(b) They do not need to store water.
(c) They keep the plant afloat.
(d) They look pretty.

In terrestrial plants, roots normally play a very important role in the absorption of nutrients and water from the soil. However, in aquatic plants, roots are much reduced in size. Some of these plants have narrow and thin ribbon-like leaves. These can bend in the flowing water. In some submerged plants, leaves are often highly divided.
Why do aquatic plants have a root system which is not very well developed?
(a) So that they can be pulled out easily.
(b) It helps them float.
(c) Since they grow in water they don't need long roots to absorb water.
(d) They do not need to absorb minerals.