Matter in Our Surroundings — Science STD 9 — Question

Name any cell organelle which is non-membranes.

Name the laws involved in the following situation:
The sum of products of masses and velocities of two moving bodies before and after their collision remains the same.

From a rifle of mass 4kg, a bullet of mass 50g is fired with an initial velocity of 35m s^-1 . Calculate the initial recoil velocity of the rifle.

The number of protons, neutrons and electrons in particles A to E are given below:

Particle	Protons	Neutrons	Electrons
A	17	18	17
B	3	4	2
C	18	22	18
D	17	20	17
E	9	10	10

Give reasons, find a pair of isotopes from the above particles.

What name is given to the repetition of sound caused by the reflection of sound waves?

Aditya added 1-2 drops of iodine to three test tubes A,B and C, containing 2ml of food samples. A dark blue-black colour appeared in test tubes A and B. The correct order of food samples taken in test tubes A, B and C is:

1. Rice, dal, potato.
2. Rice, potato, dal.
3. Potato, dal, rice.
4. Dal, rice, potato.

Give one example of diffusion of gases in a liquid.

What name is given to the product of mass and velocity of a body?

Name the process which is used in milk dairies to separate cream from milk.

State whether iron is a micronutrient with respect to plants.