326,427 views
28 votes
28 votes
A car travels for 10s at a steady speed of 20 m/s along a straight road. The traffic lights ahead change to red, and the car slows down with a constant deceleration, so that it halts after a further 8s.

User Federico Rubbi
by
3.0k points

1 Answer

25 votes
25 votes

Answer:

The right solution is "2.5 m/s²". A further explanation is given below.

Step-by-step explanation:

The given values are:

Initial velocity,

= 20 m/s

Final velocity,

= 0 m/s

Time,

= 8 s

As we know,


Acceleration=(Final \ velocity-Initial \ velocity)/(2)

On substituting the values, we get


=(0-20)/(8)


=(-20)/(8)


=-2.5 \ m/s^2

User MetaEd
by
3.0k points