Matter in Our Surroundings — Science STD 9 — Question

A fielder pulls his hands backwards after catching the cricket ball. This enables the fielder to:

1. Exert larger force on the ball.
2. Reduce the force exerted by the ball.
3. Increase the rate of change of momentum.
4. Keep the ball in hands firmly.

The isotopes of an element contain:

In which of the following cases of motion, the distance moved and the magnitude of displacement are equal?

Which of the following is parasitic protozoan?

1. Amoeba.
2. Entamoeba.
3. Euglena.
4. Paramecium.

Two objects of different masses falling freely near the surface of moon would:

A block of mass 10kg is dropped from a height of 10m from the earth's surface and it falls onto a vertical heli spring of stiffness 5000N/ m and length 50cm as shown in the figure. The compression of the springs is (Take, g = 10m/ s)

Following are a few definitions of osmosis.
Read carefully and select the correct definition:

Rahul is playing the drums. Then which of the following characteristics of sound would result in increase in loudness?

On converting 25°C, 38°C and 66°C to Kelvin scale, the correct sequence of temperature will be:

An object oscillates 50 times in one second. What would be its frequency?