2points
which of the following objects exhibit two-dimensional motion?
check all that apply.
a. an object that's thrown horizontally off a cliff and allowed to fall
o
b. an object thrown upward at an angle
o
c. an object dropped from rest
o
d. an object thrown vertically upward
submit

A. An object that's thrown horizontally off a cliff and allowed to fall

B. An object thrown upward at an angle

Explanation:

An object exhibits a two-dimensional motion if it can be described by both x and y coordinate components.This means you can describe it using a vector with the horizontal and vertical components.For example,a graph of a body that moves with a constant velocity,the sum of the velocities in the x and y directions can describe this object's position.The same with kicking a ball.The ball will rise up at an angle, where you will have the horizontal component in the x-axis direction and the vertical component in the y-axis direction.

So for the case of this question, when an object is thrown horizontally, the horizontal component is initiated which will be represented by the x-axis vector.When it is allowed to fall down, the vertical component is initiated, in this case it will be a negative vector.An object thrown upward at an angle behaves like a ball kicked at an angle.

work: w = fd (given)

work done by chet   =50*1 = 50 j

work done by mika =40*2 = 80 j

work done by sara =30*1.5 = 45 j

work done by bill =60*0.5 = 30 j

students in order from the greatest amount of work done to the least is mika> chet> sara> bill

hence option (b) is correct.