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A ball is rolling down a slope at a steady speed. Which of the following statements is correct?

A Frictional force is greater than the forward force.
B There is an unbalanced force downwards.
C There are no forces acting on the ball.
D The forces acting on the ball are balanced.

Which of the following is a correct match of the everyday object and the simple machine involved in its functioning?

ASteering of a car - Pulley
BEscalator - Wedge
CStaircase - Inclined plane
DHospital ramp - Wheel and axle

Read the given conversation.



Which of the these statements is correct?

AX is ruby and Z is tungsten.
BY is granite and Z is quartz.
CX is diamond and Y is silica.
DY is graphite and Z is tungsten.

A convex mirror of radius of curvature R produces an image (1 / 2N + 1)^th of the size of the object. The distance of the image from the mirror is

ANR
B2 NR
CNR / (2N+1)
DNR / 2(2N+1)

Given below is a list of few harmful effects on humans.
(i) Cancer
(ii) Cataract in eyes
(iii) Lowering of body's resistance to diseases
(iv) Increased mortality of developing embryo
Which of these are caused due to ozone depletion?

A(i) and (iii) only
B(ii) and (iv) only
C(iii) and (iv) only
D(i), (ii), (iii) and (iv)

A boy of mass 50 kg runs up a flight of 120 stairs, each measuring a height of 25 cm, in one minute and 40 seconds. If g = 10 m s^-2, the power of the boy is

A 150 W
B 750 W
C 500 W
D 250 W

Refer to the given figures showing seeds/fruits ofthree different plants.

Select the option which contains plants that can replace X, Y and Z, respectively based on the mode of dispersal of their seeds.

AX - Lotus; Y - Beans; Z - Calotropis
BX - Castor; Y - Coconut; Z - Acer
CX - Hiptage; Y - Balsam; Z - Cocklebur
DX - Mango; Y - Cotton; Z - Maize

The given figure shows the movement of food through the oesophagus. This movement is aided by the muscles of the oesophagus in a wave-like action called


A Diapedesis
B Peristalsis
C Rumination
D Muscularisation.

The given list shows the five steps needed to do a starch test but in a random order.
(i) Pluck a leaf from the plant.
(ii) Leave a potted plant out in the Sun for a few hours.
(iii) Boil the leaf in alcohol.
(iv) Put the leaf in boiling water for 2 minutes.
(v) Wash the leaf and then add a few drops of iodine solution over it.
Select the option with correct order of these steps.

A (i), (ii), (iii), (iv), (v)
B (i), (ii), (iv), (iii), (v)
C (ii), (i), (v), (iv), (iii)
D (ii), (i), (iv), (iii), (v)

A student performed the first set of experiments with four test tubes containing solutions and metal pieces as indicated in the figure. In the second set of experiments, the metal pieces are interchanged between test tubes P and Q and also between test tubes R and S.

In which test tube(s), no reaction will occur in both sets of experiments?

A P and Q
B R
C S
D R and S.