Question #b2ebb

1 Answer
Feb 6, 2017

Answer:

I got #2.6m#

Explanation:

I would say that the Elastic Potential Energy of the spring is converted into Kinetic Energy for the brick and so we have:
#1/2kx^2=1/2mv^2#
rearranging:
#v=xsqrt(k/m)=0.25sqrt(1250/1.5)=7.2m/s# which should be the velocity with which the brick leaves the spring.
Using Kinematics we have that:
#v_f^2=v_i^2=2ah#
where:
#v_f=0# at the top of the trajectory;
#v_i=7.2m/s#
#g=-9.8m/s^2# is the downwards acceleration of gravity;
#h# is the eight reached.
So we get:
#0=(7.2)^2-2*9.8h#
rearranging:
#h=(7.2)^2/(2*9.8)=2.6m#