L. The earth is not spherical but elliptical
in shape.
II. Variation in latitude and longitude.
III. Rotation of the earth on its axis.
IV. Variation in the density of the earth.
On which combination of the above does the weight
of an object vary on the earth's surface?
A. I, II, III and IV.
B. II, III and IV only
C. I, II and III only
D. I and II only

As a science fair project, you want to launch an 950g model rocket straight up and hit a horizontally moving target as it passes 33.0m above the launch point. The rocket engine provides a constant thrust of 20.0N . The target is approaching at a speed of 18.0m/s . At what horizontal distance between the target and the rocket should you launch?

= 43.56m

Explanation:

acceleration =

(20 - (0.95 * 9.8) )/ (0.95)

= 10.68 / 0.95

= 11.24 m/s²

we use

s = ut + (1/2) at²

Given that

s= 40

u =0  

s = 0 * t + (1/2) (11.24)t²

t = √(66/1.24)

t = √5.87

t = 2.42sec

hence

Horizontal distance = 18 * 2.42

= 43.56m