Author Question: A 1.2-kg mass is projected from ground level with a velocity of 30 m/s at some unknown angle above ... (Read 138 times)

faduma · **on:** Jul 28, 2018

A 1.2-kg mass is projected from ground level with a velocity of 30 m/s at some unknown angle above the horizontal. A short time after being projected, the mass barely clears a 16-m tall fence. Disregard air resistance and assume the ground is level. What is the kinetic energy of the mass as it clears the fence?
a. 0.35 kJ
b. 0.73 kJ
c. 0.40 kJ
d. 0.68 kJ
e. 0.19 kJ

Question 2

A 0.80-kg object tied to the end of a 2.0-m string swings as a pendulum. At the lowest point of its swing, the object has a kinetic energy of 10 J. Determine the speed of the object at the instant when the string makes an angle of 50 with the vertical.
a. 5.6 m/s
b. 4.4 m/s
c. 3.3 m/s
d. 5.0 m/s
e. 6.1 m/s