Class 9 Physics

Krishna performs an experiment to establish the relation between weight of a rectangular wooden block lying on a horizontal surface and minimum force required to jsut move it using a spring balance. If the weight of the wooden block is 300 gwt and two known weights of 100 gwt each are to be successively plcaed on the wooden block to take more readings, then which one of the following spring balances would you select to obtain best result. It is known that a force of 90 gwt is required to just move the block on the surface.

(a) Range 0-100 gwt; least count 1 gwt
(b) Range 0-200 gwt; least count 2 gwt
(c) Range 0-250 gwt; least count 2 gwt
(d) Range 0-500 gwt; least count 2 gwt

Give reason for your answer.

SUB : BIOLOGY

DAY 1 : Prepare a model of plant cell by using household materials like rice,

plastic bottles, wires, cardboard etc..

DAY 2 : Prepare a venn diagram of plant cell and animal cell ( similarities in

middle & differences in side )

DAY 3 : Make a flow chart of Tissues ( plants and animals) by using printed

diagrams or coloured diagrams

DAY 4 : Prepare a note on Types of tissues and there location and functions in a

tabular form

Prepare a plant cell model by household materials. Like rice ,plastic,cardboard.etc."*"

The cell theory states that

• A. All cells have nuclei.
• B. All cells are totipotent.
• C. Cells reproduce by mitosis.
• D. Cells are the basic structural units of living beings.

List the point of difference between Homogeneous and Heterogeneous mixtures

Turmeric is a natural indicator. On adding its paste to acid and base separately, which color is observed?

A. yellow in both acid and base

B. yellow in acid and red in the base

C. Pink in acid and yellow in the base

D. Red in acid and blue in the base.