Using a Calculator
Keep the following tips in mind when solving problems that require a calculator. Write down the equation that you will be solving before using the calculator. Next, substitute the known values for each term in the equation. Then, enter the numbers into your calculator and calculate the answer. It is also important to become familiar with the order in which your calculator performs operations. Most calculators operate using an algebra-based operating system. If time permits, double-check your answer by performing the calculations a second time.
What is the acceleration of a 1200-kg car acted on by a net force of 250 N?
0.21 m/s2
2.4 m/s2
4.8 m/s2
950 m/s2
300,000 m/s2
(Answer: A)
Choose the letter that best answers the question or completes the statement.
Which of the following correctly lists friction types (excluding fluid friction) from weakest to strongest?
sliding, static, magnetic
static, rolling, sliding
weak, strong, nuclear
rolling, sliding, static
static, sliding, rolling
Which statement about an object falling at terminal velocity is TRUE?
Unbalanced forces act on the object.
The net force acting on the object is zero.
The object is accelerating.
The object is traveling in a circular path.
No fluid friction acts on the object.
An object changes direction as it moves. Which of the following is FALSE?
The acting net force is not zero.
An unbalanced force acts on the object.
The object is accelerating.
A centripetal force must act on the object.
The object's inertia remains unchanged.
Which has the greatest momentum?
a huge boulder at rest
a small pebble that is tossed into the air
a baseball after it is hit with a bat
a small pebble at rest
a car traveling on a highway
Use the diagram below to answer Questions 5 and 6. The diagram shows how five forces act on a wooden crate as it slides across the floor.
5. If A = 60 N, B = 20 N, C = 30 N, D = 30 N, and E = 30 N, which of the following statements is FALSE?
A net force of 50 N acts on the crate and the crate moves to the right.
The crate accelerates to the right.
The net force in the vertical direction is zero.
Force C represents the weight of the crate.
Forces C and E represent balanced forces acting in the vertical direction.
Which force represents the sliding friction force?
A
B
C
D
E