2027 AP Physics 1 Updates

Since the publication of Barron’s AP Physics 1 Premium, 2027 Edition, the College Board has announced minor updates to the format of the May 2027 exam. These updates affect only the number of multiple-choice questions and the timing for both sections of the exam; they do not change the course content, skills assessed, or topics students are expected to know for the exam.

Barron's AP Physics 1 Premium, 2027 Edition remains a comprehensive resource for AP Physics 1 exam preparation, which provides thorough content review, extensive AP-style practice, and proven test-taking support.

The updates are as follows:

• Section I now has 42 multiple-choice questions (an increase of 2 questions).
• Students now have 85 minutes to complete the multiple-choice questions in Section I (an increase of 5 minutes).
• Students now have 95 minutes to complete the free-response questions in Section II (a decrease of 5 minutes).

To reflect the updated exam format, below are two additional multiple-choice questions (Questions 41 and 42) for each practice test in the book, along with their respective answer explanations. In addition, both online tests that accompany this book have been revised to reflect the exam format updates. 

Questions for Practice Test 1

 41. A small, rigid ball is completely submerged far below the surface of a large body of water. After the ball is released, it is observed to accelerate upwards. Which statement best explains this acceleration?  

(A)  The object experiences a decreasing gravitational force as it rises.

(B)  The object’s density is changing as it rises.

(C)  The object experiences a decreasing buoyant force as it rises.

(D)  The pressure on the bottom of the ball is greater than the pressure on the top of the ball.

42. A cart moves along a straight track. The velocity–time graph for the cart is a straight line 

with a positive slope. Which statement best describes the motion of the cart?

(A) The cart moves at a constant speed in the positive direction.

(B) The cart moves in the positive direction while slowing down.

(C) The cart moves in the negative direction with decreasing speed.

(D) The cart moves in the negative direction with increasing speed.

 Questions for Practice Test 2

41.  A block is pushed against a vertical wall with a horizontal force. The block remains at rest. 

Which change would increase the minimum force needed to keep the block from sliding down?

(A) Increasing the coefficient of static friction between the block and the wall
(B) Decreasing the mass of the block
(C) Decreasing the coefficient of static friction between the block and the wall
(D) Decreasing the coefficient of kinetic friction between the block and the wall

 42. A student pulls a box across a rough horizontal floor using a rope that makes an angle above the horizontal. As the angle of the rope increases while the magnitude of the pulling force remains constant, what happens to the work done by friction per meter across the floor?

(A) It decreases because the horizontal component of the pulling force decreases.

(B) It decreases because the box will slow down.

(C) It decreases because the normal force on the box decreases.

(D)  It increases.

Answer Explanations for Practice Test 1

41. (D) Acceleration is due to net force. The net force is found by taking the difference between the downward force of gravity and the upward buoyant force.  Since the mass of the ball is not changing, the gravitational force is constant.  The buoyancy force is upward and must be greater than the gravitational force in order to cause an upward acceleration.  The buoyancy force is the result of the difference between the slightly higher pressure the fluid exerts on the bottom of the ball (since it is deeper below the surface of the water) than the pressure exerted on the top of the ball (slightly closer to the surface of the water, thus the weight of the water above is less).  Note that since the ball is rigid, its density is unlikely to change and, if it were to change, it would most likely increase slightly, which would lead to a slight increase in the buoyancy force.

42.  (C) A positive slope on a velocity vs time graph tells us that the acceleration of the object is positive. Specifically, the initial velocity subtracted from the final velocity must be a positive number.  For our four cases:

•  The cart moves at a constant speed in the positive direction: Acceleration is zero
• The cart moves in the positive direction while slowing down: Acceleration is negative
• The cart moves in the negative direction with decreasing speed: Acceleration is positive
• The cart moves in the negative direction with increasing speed: Acceleration is negative

 Answer Explanations for Practice Test 2

41. (C) The normal force exerted by the wall on the block, which results from the horizontal push, is what allows the block to remain at rest vertically. The block will stay in place as long as the upward force of static friction between the block and the wall is equal to the downward force of gravity.

Static friction is proportional to the normal force. The coefficient of static friction indicates the maximum possible fraction of the normal force that can act as friction to maintain static equilibrium. Since the block is being held in place with the minimum required force, the static friction force is already at its maximum. Increasing the coefficient of static friction would not change the fact that the block is already held in place, but lowering the coefficient would require a greater normal force to provide enough friction.

A lower mass would result in a lower gravitational force, which would decrease the amount of friction needed to hold the block in place. The coefficient of kinetic friction applies only after the block begins to slide, so it is not relevant to this problem.

  42. (C) The force of friction is proportional to the normal force. As the angle of the rope increases, the forward horizontal component of the tension decreases, while the upward vertical component increases. As a result, the upward normal force exerted by the floor on the box decreases.

Since the normal force decreases, the frictional force also decreases. This leads to a decrease in the work done by friction per meter.

Because we do not know the acceleration of the box, we cannot use the horizontal pulling force alone to determine the work done by friction. We also cannot determine whether the box is speeding up or slowing down.