Selina solutions concise physics class 7 icse Solutions for Chapter 1 physical quantities and measurement

Q1) The length, breadth and height of a water tank are 5m,2.5m and 1.25m respectively. Calculate the capacity of the water tank in (a) m^3 (b) litre.

Q2) A solid silver piece is immersed in water contained in a measuring cylinder. The level of water rises from 50ml to 62ml. Find the volume of silver piece.

Q3) Find the volume of a liquid present in a dish of dimensions 10cm\times10cm\times5cm.

Q4) A rectangular field is of length 60m and breadth 35m. Find the area of the field.

Q5) Find the approximate area of an irregular lamina of which boundary line is drawn on the graph paper shown in fig 1.16. below.

Q6) A piece of brass of volume 30 cm3 has a mass of 252 g. Find the density of brass in (i) g cm-3, (ii) kg m-3

Q7) The mass of an iron ball is 312g. The density of iron is 7.8\ g\ cm^{-3}. Find the volume of the ball.

Q8) A cork has a volume of 25cm^3. The density of cork is 0.25\ g\ cm^{-3}. Find the mass of cork.

Q9) The mass of 5 litre of water is 5 kg. Find the density of water in g\ cm^{-3}.

Q10) A cubical tank of side 1m is filled with 800 kg of a liquid. Find (i) the volume of the tank, (ii) the density of liquid in kg\ m^{-3}

Q11) A block of iron has dimensions 2m\times0.5m\times0.25m. The density of iron is 7.8\ g\ cm^{-3}. Find the mass of block.

Q12) The mass of a lead piece is 115g. When it is immersed into a measuring cylinder, the water level rises from 20ml mark to 30ml mark. Find (i) the volume of the lead piece (ii)the density of the lead in kg\ m^{-3}

Q13) The density of copper is 8.9 g\ cm^{-3}. What will be its density in kg\ m^{-3}

Q14) A car travels a distance of 15km in 20 minute. Find the speed of the car in (i) km\ h^{-1} (ii) m\ s^{-1}

Q15) How long a train will take to travel a distance of 200 km with a speed of 60 km\ h^{-1}?

Q16) A boy travels at a speed of 10 m\ s^{-1} for 30 minute. How much distance does he travel?

Q17) Express 36 km\ h^{-1} in m\ s^{-1}.

Q18) Express 15 m\ s^{-1} in km\ h^{-1}.

Q1) Write true or false for each statement

(a) The SI. unit of volume is litre.

(b) a measuring beaker of capacity 200 ml can measure only 200 ml volume of a liquid.

(c) cm^2 is a smaller unit of area than m^2.

(d) equal volumes of two different substances have equal masses.

(e) the SI unit of density is g\ cm^{-3}.

(f) 1 g\ cm^{-3} = 1000 kg\ m^{-3}.

(h) the speed 5 m\ s^{-1} is less than 25 km\ h^{-1}.

(i) the SI unit of speed is m\ s^{-1}.

Q2) Fill in the blanks: (a) 1 m^3 = ______ cm^3

(b) The volume of an irregular solid is determined by the method of _____.

(c) Volume of a cube = ________ (d) The area of an irregular lamina is measured by using a ______.

(e) Mass = density \times ______. (f) The S.I. unit of density is _____.

(g) 1 g\ cm^{-3} = ______ kg\ m^{-3}. (h) 36 km\ h^{-1} = _____ m\ s^{-1}.

(i) Distance travelled d = _______ \times time t.

Q3) Match the following:

Q4) Select the correct alternative:

(a) One litre is equal to:

1. 1 cm^{-3}

2. 1 m^3

3. 10^{-3}\ cm^3

4. 10^{-3}\ m^3

(b) A metallic piece displaces water of volume 15 ml. The volume of piece is:

1. 15 cm^3

2. 15 m^3

3. 15\times10^3\ cm^3

4. 15\times10^3\ cm^3

(c) A piece of paper of dimensions 1.5m 20 cm has area:

1. 30 m^2

2. 300 cm^2

3. 0.3 m^2

4. 3000 m^3

(d) The correct relation is:

1. d\ =\ M\times V

2. M\ =\ d\times Y

3. V=d\times M

4. d = M + V

(e) The density of alcohol is 0.8 g\ cm^{-3}. In S.I. unit, it will be:

1. 0.8 kg\ m^{-3}

2. 0.0008 kg\ m^{-3}

3. 800 kg\ m^{-3}

4. 8\times10^3\ kg\ m^{-3}

(f) The density of aluminium is g\ cm^{-3} and brass is 8.4 g\ cm^{-3}. For the same mass of volume of:

1. both will be same

2. aluminium will be less than that of brass

3. aluminium will be more than that of brass

4. nothing can be said

(g) A block of wood of density 0.8 g\ cm^{-3} has a volume of 60 cm^3. The mass of block will be:

1. 60.8 g

2. 75 g

3. 48 g

4. 0.013 g

(h) The correct relation for speed is

1. Speed = distance x time

2. speed = distance/time

3. speed = time/distance

4. speed = 1/ distance x time

(i) A boy travels a distance of 150 m in 1 minutes. His speed is:

1. 150 m\ s^{-1}

2. 2.5 m\ s^{-1}

3. 25 m\ s^{-1}

4. 9 m\ s^{-1}

Q1) Define the term volume of an object.

Q2) State and define the S.I. unit of volume.

Q3) State two smaller units of volume. How are they related to the S.I.unit?

Q4) How will you determine the volume of a cuboid? Write the formula you will use.

Q5) Name two devices which are used to measure the volume of an object. Draw their neat diagrams.

Q6) How can you determine the volume of an irregular solid (say a piece of brass)? Describe in steps with neat diagrams.

Q7) You are required to take out 200ml of milk from a bucket full of milk. How will you do it?

Q8) Describe the method in steps to find the area of an irregular lamina using a graph paper.

Q9) Define the term density of a substance.

Q10) State the S.I. and C.G.S. units of density. How are they interrelated?

Q11) The density of brass is 8.4 g cm^3. What do you mean by the statement?

Q12) Arrange the following substance in order of their increasing density: (a) iron (b) cork (c) brass (d) water (e) mercury

Q13) How does the density of water changes when :

(a) it is heated from 0°C to 4°C.

(b) it is heated from 4°C to 10°C ?

Q14) Write the density of water at 4°C.

Q15) Explain the meaning of the term speed.

Q16) Write the S.I unit of speed.

Q17) A car travels with a speed 12 m\ s^{-1}, while a scooter travels with a speed 36 km\ h^{-1}. Which of the two travels faster?