Tiêu đề Integrated Series 7th Class Physics - Solutions.pdf ✅

Class 7 – Physics | I-7 Physical Quantities and Measurements 1 1.Physical Quantities and Measurements Solutions _______________________________________________ LEVEL – I 1. Correct option: (A) Fundamental physical quantities are the quantities whose measurement does not depend on other physical quantities. For example, quantities Length, time and mass are measured independently and hence they are fundamental physical quantities. 2. Correct option: (A) In general magnitude of a physical quantity (P)= numerical value(N) × size of it’s unit(U). Or P=NU For example. If length of a rod = 3 m Then 3 = numerical value 1m = size of the unit 3. Correct option: (A) SI system is the internationally accepted system of units for measurements. The SI, with standard scheme of symbols, units and abbreviations, was developed and recommended by General conference on weights and measures in 1971 for international usage in scientific, technical, industrial and commercial work. There are seven fundamental quantities in SI system: Mass, length, Time, Temperature, Electric current, Luminous Intensity, Quantity of matter and two Supplementary physical quantities. 4. Correct option: (B) Given: edge/side of cube =5m Total surface area of cube = 6 x (side) 2 = 6 x (5m) 2 = 6 x 25 m2 Total surface area of cube = 150m2 5. Correct option: (A) In order to find the area of a rose leaf the best option: is a centimetre graph paper. It would be suitable to find the area enclosed by the smaller portions of the rose leaf.
Class 7 – Physics | I-7 Physical Quantities and Measurements 2 6. Correct option: (A) Given: outer radius of the ring(r1) =4cm Inner radius of the ring(r2)=3cm Area of ring = π(r1 2 − r2 2 ) =3.14(4 2 − 3 2 )cm2 =3.14(16 − 9)cm2 = 3.14x 7cm2 Area of the ring =21.98cm2 7. Correct option: (D) Given: Area of parallelogram =144cm2 Height=18 cm To find: length of base Area of parallelogram = base x height 144cm2 = base x 18cm 144 18 cm = base 8cm = base Hence, the length of base is 8 cm. 8.Correct option: (A) Volume is the amount of space occupied by a three dimensional shape, measured in cubic units. SI unit of volume is m3 (cubic meter) 9. Correct option: (C) Volume of block of wood/cuboid = length x breadth x height =20 cm x 10 cm x 8 cm = 1600cm3 10. Correct option: (B) Tank is in the shape of cuboid. Given: Length = 1.4m Width =1m Height/depth=0.7m