Solve this.
Q.53. A small solid sphere falls with a terminal velocity of 30 m/sec. In vacuum, the terminal velocity will be
(a) less than 30 m/s
(b) more than 30 m/s
(c) equal to 30 m/s
(d) no terminal velocity
Q.54. A ray of light incident at an angle 45$°$ on an air-glass interface gets reflected. The angle of deviation of the ray is
(a) 45$°$
(b) 180$°$
(c) 135$°$
(d) None of these

Dear Student ,
53. The correct answer is option (D) - zero, or no terminal velocity .

The terminal velocity of a falling is inversely proportional to the density of the fluid and the drag coefficient. So, an object moving in a denser fluid will have a lesser terminal velocity due to increased drag effects and vice versa. 

Now, as vacuum exerts no viscous drag force the terminal velocity will be zero.

Kindly ask different question in different posts .
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