Question

A body is projected horizontally with speed 20 m/s. What will be its speed nearly after 5 sec?

• A. 54 m/s
• B. 20 m/s
• C. 50 m/s
• D. 70 m/s

Answer 1

Answer: (A)

54 m/s

Answer 2

v_x = u = 20 m/s

v_y = u_y + gt = 0 + 10 × 5 = 50 m/s

v = $\sqrt { \mathrm { u } _ { \mathrm { x } } ^ { 2 } + \mathrm { u } _ { \mathrm { y } } ^ { 2 } } = \sqrt { ( 20 ) ^ { 2 } + ( 50 ) ^ { 2 } }$