Question

An antelope moving with constant acceleration covers the
distance between two points 70.0 m apart in 7.00 s. Its speed as it
passes the second point is 15.0 m/s. (a) What is its speed at the first
point? (b) What is its acceleration?​

Answer 1

Explanation:

the speed at the first point is:

$speed = \frac{distance}{time}$

=

$speed = \frac{70}{7} = 10$

therefore,speed at first point is 10m/s

during passing the second it's acceleration is:

first we have to find time of second pass

therefore,

$speed = \frac{distance}{time}$

=

$time = \frac{distnce}{speed}$

=

$time = \frac{70}{15} = \frac{14}{3} = 4.66$

therefore,5sec

so,

$a = \frac{v - u}{t}$

=

$a = \frac{0 - 15}{5} = \frac{ - 15}{5} = - 3$

therefore,acceleration=3m/s