A table tennis ball has radius (3/2) × 10−2 m and mass (22/7) × 10−3 kg. It is slowly pushed down into a swimming pool to a depth of 𝑑 = 0.7 m below the water surface and then released from rest. It emerges from the water surface at speed 𝑣, without getting wet, and rises up to a height 𝐻. Which of the following option(s) is(are) correct? [Given: 𝜋 = 22/7, 𝑔 = 10 m s −2 , density of water = 1 × 103 kg m−3 , viscosity of water = 1 × 10−3 Pa-s.] (A) The work done in pushing the ball to the depth 𝑑 is 0.077 J. (B) If we neglect the viscous force in water, then the speed 𝑣 = 7 m/s. (C) If we neglect the viscous force in water, then the height 𝐻 = 1.4 m. (D) The ratio of the magnitudes of the net force excluding the viscous force to the maximum viscous force in water is 500/9.
A table tennis ball has radius (3/2) × 10−2 m and mass (22/7) × 10−3 kg. It is slowly pushed down into a swimming pool to a depth of 𝑑 = 0.7 m below the water surface and then released from rest. It emerges from the water surface at speed 𝑣, without getting wet, and rises up to a height 𝐻. Which of the following option(s) is(are) correct? [Given: 𝜋 = 22/7, 𝑔 = 10 m s −2 , density of water = 1 × 103 kg m−3 , viscosity of water = 1 × 10−3 Pa-s.] (A) The work done in pushing the ball to the depth 𝑑 is 0.077 J. (B) If we neglect the viscous force in water, then the speed 𝑣 = 7 m/s. (C) If we neglect the viscous force in water, then the height 𝐻 = 1.4 m. (D) The ratio of the magnitudes of the net force excluding the viscous force to the maximum viscous force in water is 500/9.