NEET Practice Questions (MCQs) with Answers & Solutions

Points to Ponder, point 8, states: 'Although the gravitational force between two particles is central, the force between two finite rigid bodies is not necessarily along the line joining their centre of mass. For a spherically symmetric body however the force on a particle external to the body is as if the mass is concentrated at the centre and this force is therefore central.'

The text on page 135 and Points to Ponder, point 5, explicitly states: 'The gravitational potential energy associated with two particles of masses $m_1$ and $m_2$ separated by distance by a distance r is given by $V = - G m_1 m_2 / r$ (if we choose V = 0 as $r \rightarrow \infty$ )'.

Equation (7.12) on page 133 is given as $g = G M_E / R_E^2$. In this equation, G is the universal gravitational constant, M_E is the mass of the Earth, and R_E is the radius of the Earth. F represents force, not a constant in this context.

Points to Ponder, point 9, and Exercise 7.1 (a) explicitly state: 'Gravitational shielding is not possible.'

Problems 7.17 and 7.19 consistently mention 'G = $6.67 \times 10^{-11} \text{ N m}^2 \text{ kg}^{-2}$'. This translates to $N \text{ m}^2 / \text{ kg}^2$.

Points to Ponder, point 1, states: 'In considering motion of an object under the gravitational influence of another object the following quantities are conserved: (a) Angular momentum (b) Total mechanical energy. Linear momentum is not conserved'.

Points to Ponder, point 4, clearly states: 'An astronaut experiences weightlessness in a space satellite. This is not because the gravitational force is small at that location in space. It is because both the astronaut and the satellite are in 'free fall' towards the Earth.'

The NCERT text states: 'Intentional or voluntary termination of pregnancy before full term is called medical termination of pregnancy (MTP) or induced abortion.'

The context mentions: 'Nearly 45 to 50 million MTPs are performed in a year all over the world which accounts to 1/5th of the total number of conceived pregnancies in a year.'

The NCERT text clearly states: 'Government of India legalised MTP in 1971 with some strict conditions to avoid its misuse.'