Question

3.3.2 test (cst): forces
question 4 of 20
this table shows the weights of four different objects that are sitting on the floor.
a person tries to lift each object with a force of 18 n, upward. which statement is supported by the data in the table?
a. all of the objects will move, and object 2 will accelerate upward the fastest.
b. none of the objects will move, but the normal force on all of the objects will increase.
c. objects 1 and 2 will not move, and objects 3 and 4 will accelerate upward.
d. objects 1 and 2 will move downward, and objects 3 and 4 will move upward.

Explanation:

Step1: Analyze the condition for an object to move upward

An object will move upward if the upward - lifting force \(F = 18N\) is greater than its weight \(W\).

Step2: Check each object

• Object 1: \(W_1=25N\gt18N\), so it will not move.
• Object 2: \(W_2 = 33N\gt18N\), so it will not move.
• Object 3: \(W_3=16N\lt18N\), so it will accelerate upward (\(F_{net}=18 - 16=2N\) upward).
• Object 4: \(W_4 = 8N\lt18N\), so it will accelerate upward (\(F_{net}=18 - 8 = 10N\) upward).

Answer:

C. Objects 1 and 2 will not move, and objects 3 and 4 will accelerate upward.