Question #13bdf

2 Answers
Jan 25, 2018

We can use the equation #v=u+at# where:

#v=7# #ms^-1# (final velocity)
#u=0# #ms^-1# (initial velocity)
#a=7.9# #ms^-2# (acceleration)
#t=?# #s# (time)

Rearranging, #t=(v-u)/a=(7-0)/7.9=0.89# #s#

Jan 25, 2018

Answer:

The time required is 0.886 s.

Explanation:

Use the suvat formula

#v = u + a*t#

Plug in the data and solve for t.

#7 ms^-1 = 0 + 7.9 ms^-2*t#

#7.9 ms^-2*t = 7 ms^-1#

#t = (7 ms^-1)/(7.9 ms^-2) = 0.886 s#

I hope this helps,
Steve