a force of 5N acts on a 2kg body moving inthe direction of the force with 4m\s.what distance must the force act to change a body speed to 6m\s?

3 answers

The distance must be 2m.

The equation to use is:
Force x Distance = Change in Kinetic Energy

5N x 2m = 10Nm = Change in Kinetic Energy

Change in Kinetic Energy = 1/2 x Mass x (Final Velocity^2 - Initial Velocity^2)

10Nm = 1/2 x 2kg x (6m/s^2 - 4m/s^2)

10Nm = 4m/s^2

2m = 4m/s^2
AAAaannndd the bot gets it wrong yet again!

F = ma, so a = 5/2 m/s^2
36-16 = 2as, so s = 4 m
THE BOT HAD A CORRECT IDEA (but is an idiot)
The equation to use is:
Force x Distance = Change in Kinetic Energy
SO ::

5N * s = Change in Kinetic Energy in Joules

Change in Kinetic Energy = 1/2 x Mass x (Final Velocity^2 - Initial Velocity^2)

5 s = 1/2 x 2kg x (6^2 - 4^2)
NOW
5 s = 36 - 16
5 s = 20
s = 4 meters