PHY 121 Exams 1-4 Questions with
complete solution 2025
2.1 When you sit on a chair, the resultant force on you is
down
up
zero
depending on your weight - correct answer ✔Up
2.2 When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly
turned off, while traveling in empty space, the starship will
stop immediately
go faster and faster.
slowly slow down, and then stop.
move with constant speed. - correct answer ✔move with constant speed.
,1.1 Starting from city A, a car drives 250 miles east to city B, then 300 miles
north to city C, and finally 700 miles west to city D. What is the distance
between city A and city D?
Question options:
600 mi
400 mi
500 mi
300 mi - correct answer ✔500mi
2.3 A 15-ton truck collides with a 1500-lb car and causes a lot of damage to
the car. Since a lot of damage is done on the car
Question options:
the truck did not slow down during the collision.
the force on the truck is greater than the force on the car.
,the force on the truck is equal to the force on the car.
the force on the truck is smaller tan the force on the car. - correct answer
✔The force on the truck is equal to the force on the car
2.4 A sports car of mass 1000 kg can accelerate from rest to 35 m/s in 1.3 s.
What is the average forward force on the car?
Question options:
1.9 × 10^5 N
2.6 × 10^2 N
2.7 × 10^4 N
3.9 × 10^3 N - correct answer ✔2.7x10^4
1.2 A new car manufacturer advertises that their car can go "from zero to sixty
in 8 s". This is a description of
Question options:
, average acceleration
average speed
instantaneous acceleration
instantaneous speed - correct answer ✔Average Acceleration
2.5 Is it possible for an object moving with a constant speed to accelerate?
Explain.
Question options:
Yes, if an object is moving it can experience acceleration
Yes, although the speed is constant, the direction of the velocity can be
changing.
No, if the speed is constant then the acceleration is equal to zero.
complete solution 2025
2.1 When you sit on a chair, the resultant force on you is
down
up
zero
depending on your weight - correct answer ✔Up
2.2 When the rocket engines on the starship NO-PAIN-NO-GAIN are suddenly
turned off, while traveling in empty space, the starship will
stop immediately
go faster and faster.
slowly slow down, and then stop.
move with constant speed. - correct answer ✔move with constant speed.
,1.1 Starting from city A, a car drives 250 miles east to city B, then 300 miles
north to city C, and finally 700 miles west to city D. What is the distance
between city A and city D?
Question options:
600 mi
400 mi
500 mi
300 mi - correct answer ✔500mi
2.3 A 15-ton truck collides with a 1500-lb car and causes a lot of damage to
the car. Since a lot of damage is done on the car
Question options:
the truck did not slow down during the collision.
the force on the truck is greater than the force on the car.
,the force on the truck is equal to the force on the car.
the force on the truck is smaller tan the force on the car. - correct answer
✔The force on the truck is equal to the force on the car
2.4 A sports car of mass 1000 kg can accelerate from rest to 35 m/s in 1.3 s.
What is the average forward force on the car?
Question options:
1.9 × 10^5 N
2.6 × 10^2 N
2.7 × 10^4 N
3.9 × 10^3 N - correct answer ✔2.7x10^4
1.2 A new car manufacturer advertises that their car can go "from zero to sixty
in 8 s". This is a description of
Question options:
, average acceleration
average speed
instantaneous acceleration
instantaneous speed - correct answer ✔Average Acceleration
2.5 Is it possible for an object moving with a constant speed to accelerate?
Explain.
Question options:
Yes, if an object is moving it can experience acceleration
Yes, although the speed is constant, the direction of the velocity can be
changing.
No, if the speed is constant then the acceleration is equal to zero.
