PHYSICS CH6 Light — Science STD 9 — Question

Solve : The mass of 40 apples in a box is 5 kg.
(i) Find the mass of a dozen of them.
(ii) Express the mass of one apple in gram.

Arun and Akash were given fertilisers and earthworm compost both to be used in the fields. Akash preferred to use earthworm compost. Why did not select the fertilizers?

Sulphuric acid is called King of Chemicals. Why is it called so?

What is the nature of the image formed by a concave mirror if the magnification produced by the mirror is +4?

Numerical Problem.

Find the mass of an object weighing 98 N

What is Bit?

While conducting experiments to study the effects of various stimuli on the plants, it was observed that the roots of a plant X grow and bend towards two stimuli A and B but bend away from a third stimulus C. The stem of the plant X however bends ” away from stimulus A and B but bends towards the stimulus C. The stimulus B is known to act on the roots due to factors related with Earth. Keeping these points in mind, answer the following questions:

Write the adaptations of mesophytes.

Photosynthesis converts energy X into energy Y.

1. What are X and Y?
2. Green plants are autotrophic in their mode of nutrition. Why?

What is lateral inversion in a plane mirror?