Question

A particle is dropped along the axis from a height 15 cm on a concave mirror of focal length 30 cm as shown in figure. The acceleration due to gravity is 10 m/s². Find the maximum speed of image in m/s –

• A. 1.2 m/s
• B. 3.5 m/s
• C. 2.25 m/s
• D. 5.5 m/s

Answer 1

Answer: (C)

2.25 m/s

Answer 2

=

= –

= 0 Ž y = $\frac { \mathrm { f } } { 6 }$

\ v_xi = $\frac { 3 } { 4 }$ $\sqrt { 3 \mathrm { fg } }$

= $\frac { 3 } { 4 } \sqrt { 3 \times 0.3 \times 10 }$

= $\frac { 9 } { 4 }$ = 2.25 m/s