Case Study Questions
Question 1:
Nakul was doing an experiment to find the radius r of a ball. For this he took a cylindrical container with radius R = 7 cm and height 10 cm. He filled the container almost half by water as shown in the figure-1. Now he dropped the ball into the container as in figure-2.
He observed that in figure-2, the water level in the container raised from P to Q i.e, to 3.4 cm.

(i) What is the approximate radius of the ball?
(a) 3 cm
(b) 5 cm
(c) 7 cm
(d) 9 cm
(ii) What is the volume of the cylinder?
(a) 1260 cm2
(b) 540 cm3
(c) 1620 cm3
(d) 1540 cm3
(iii) What is the volume of the spherical ball?
(a) 620 cm3
(b) 824.26 cm3
(c) 523.81 cm3
(d) 430.1 cm3
(iv) How many litres of water can be filled in the full container ?
(a) 1.54 litres
(b) 2 litres
(c) 5 litres
(d) 7.5 litres
(v) What is the total surface area of the spherical ball?
(a) 441.34 cm2
(b) 314.29 cm2
(c) 620 cm2
(d) 816 cm2
Answer
Answer: