Question

A body is thrown vertically up from the top of a tower with a velocity of 6 m/s Its velocity after two seconds
1) 17.6 m/s
2) 15.6 m/s
3) 13.6 m/s
4) 23.6 m/s​

Answer 1

Answer:

v=u+at

where,

u=6m/s

a=-9.8m/s² acceleration due to gravity

t=2sec

v=?

v=6-9.8(2)

v=6-19.6

v=-13.6m/s

here '-' sign indicates velocity towards ground

Answer 2

Question:

• A body is thrown vertically up from the top of a tower with a velocity of 6 m/s Its velocity after two seconds

Answer:

• The velocity of the body after 2 seconds is 13.6 m/s

Explanation:

Given that:

• A body is thrown vertically up from the top of a tower with a velocity of 6 m/s

To Find:

• The velocity of the body after the time of  seconds

Formula Used:

$\bigstar \; {\underline{\boxed{\bf{ v_{(velocity \; Final)} = u_{(velocity \; initial)} + a_{(acceleration)}t_{(time)}}}}}$

Required Solution:

• Using first equation of motion

$\leadsto \; \; {\pink{\boxed{\bf{ v = u + at }}}}$

$\red\bigstar$ Where,

• v denotes final velocity
• u denotes initial velocity
• a denotes acceleration
• t denotes time interval

$\red\bigstar$According to the question,

• A ball is thrown upwards vertically with the velocity of 6 m/s and that we should find its velocity after 2 seconds so , now as the body is projected with the initial velocity of 6 m/s and the only force acting up on it will be the acceleration due to gravity

⠀⠀⠀⠀⠀⠀⠀⠀⠀━━━━━━━━━━━━━━━━━━  

$\red\bigstar$ Here,

• Acceleration will be - 9.8 m/s [ opposite direction ]
• Initial velocity will be 6m/s
• Time period will be 2 seconds

$\\ {\purple{\bigstar\; \; {\underline{\bf{ Calculating \; the \; final \; velocity : }}}}}$

$\footnotesize{ \red{ \longrightarrow \sf Velocity_{(final)} = Velocity_{(Initial)} + acceleration_{(due \; to \; gravity)} * time_{(interval)}}}$

$\\ {\purple{\bigstar\; \; {\underline{\bf{Plugging \;in\;the \;values : }}}}}$

$\footnotesize \longrightarrow \sf v_{(final)} = u_{(initial)} + a_{(acceleration)} * t _{(time)} \\ \\ \\ \footnotesize \longrightarrow \sf v_{(final)} = 6 \; m/s - 9.8 \; m/s^2 * \; 2s \\ \\ \\ \footnotesize \longrightarrow \sf v_{(final)} = 6 m/s - 19 . 16 \; m/s \\ \\ \\ \footnotesize {\longrightarrow{\red{\underline{\underline{ \sf v_{(final)} = - 13 . 6 \; m/s }}}}}$

$\red\bigstar$ Henceforth,

• The final velocity of thee body is - 13.6 m/s

Therefore:

• The final velocity of the body is - 13.6 m/s

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