A physics student climbs a tree. To measure how high she has climbed she drops a rock. It takes 1.3 seconds for the rock to hit the ground. How many feet has she climbed?

1 Answer

She has climbed #8.3# #m#.

Explanation:

Summarise data:

#t= 1.3# #s#
#a= 9.8# #ms^-2# (acceleration due to gravity)
#s = ?# #m#
#u = 0# #ms^-1#

#s= ut + 1/2 at^2#
#s = 0 \times 1.3 + 1/2 \times 9.8 \times 1.3^2#

# s= 8.281# #m#, but we were only given two significant digits in the question, so we should only give two in the answer, so #s = 8.3# #m#.