Multiple-Choice Questions on Dynamics

1️⃣ A 5 kg block is acted upon by a 20 N force. What is its acceleration? ⚡🧱
A) 2 m/s²
B) 4 m/s²
C) 5 m/s²
D) 10 m/s²

2️⃣ Which of the following forces is considered a conservative force? 🔄⚖️
A) Friction
B) Normal force
C) Air resistance
D) Gravity

3️⃣ A 10 kg object moving at 4 m/s collides with a stationary 5 kg object. If they stick together, what is their final velocity? 🎯💥
A) 1.33 m/s
B) 2.67 m/s
C) 4 m/s
D) 6 m/s

4️⃣ If a car goes around a circular track at constant speed, what changes? 🚗🔄
A) Velocity
B) Kinetic energy
C) Momentum
D) Mass

5️⃣ A force of 30 N acts on a 3 kg object for 5 seconds. What is its change in velocity? ⚡⏳
A) 10 m/s
B) 20 m/s
C) 30 m/s
D) 50 m/s

6️⃣ A satellite orbits Earth in a circular path. What force keeps it in motion? 🛰️🌍
A) Normal force
B) Gravitational force
C) Magnetic force
D) Air resistance

7️⃣ A 15 N force stretches a spring by 5 cm. What is the spring constant? 🏗️⚖️
A) 3 N/m
B) 75 N/m
C) 300 N/m
D) 500 N/m

8️⃣ A car of mass 1000 kg accelerates from rest to 20 m/s in 5 seconds. What is the force acting on it? 🚗💨
A) 2000 N
B) 4000 N
C) 5000 N
D) 6000 N

9️⃣ Which of the following is NOT an example of rotational motion? 🔄📏
A) A spinning top
B) A wheel rotating
C) A falling ball
D) A satellite orbiting Earth

🔟 A pendulum swings back and forth. Where is kinetic energy at its maximum? ⏳🎢
A) At the highest point
B) At the lowest point
C) Midway between high and low
D) It remains constant

1️⃣1️⃣ A 4 kg object moves at 8 m/s. What is its kinetic energy? 🔋⚡
A) 16 J
B) 32 J
C) 64 J
D) 128 J

1️⃣2️⃣ Which of these statements about momentum is correct? 🚀🛑
A) It is a scalar quantity
B) It is conserved in all collisions
C) It depends only on mass
D) It is measured in Newtons

1️⃣3️⃣ An object in free fall has constant…? 🌍⬇️
A) Velocity
B) Acceleration
C) Momentum
D) Force

1️⃣4️⃣ A 2 kg ball moving at 6 m/s collides with a 4 kg stationary ball. If the 2 kg ball stops, what is the velocity of the 4 kg ball after collision? 🎱💥
A) 1 m/s
B) 2 m/s
C) 3 m/s
D) 4 m/s

1️⃣5️⃣ The force required to maintain an object in uniform circular motion is called? 🔄⚖️
A) Centripetal force
B) Gravitational force
C) Frictional force
D) Magnetic force

1️⃣6️⃣ A roller coaster at the highest point has maximum…? 🎢⬆️
A) Kinetic energy
B) Momentum
C) Potential energy
D) Force

1️⃣7️⃣ A 50 N force is applied at a 30° angle to move a box. What component of force acts in the direction of motion? 📦🔢
A) 25 N
B) 30 N
C) 43.3 N
D) 50 N

1️⃣8️⃣ If an object experiences a net force of zero, it must be…? ⚖️🚫
A) Moving with constant velocity
B) Accelerating
C) At rest
D) Both A and C

1️⃣9️⃣ Which force opposes motion and converts kinetic energy into heat? 🔥⚡
A) Normal force
B) Friction
C) Tension
D) Gravity

2️⃣0️⃣ A 3 kg object moving at 5 m/s hits a wall and stops in 0.2 seconds. What is the force exerted on it? 🚧⚠️
A) 15 N
B) 25 N
C) 50 N
D) 75 N

Answer

1️⃣ C) 5 m/s²
2️⃣ D) Gravity
3️⃣ B) 2.67 m/s
4️⃣ A) Velocity
5️⃣ B) 20 m/s
6️⃣ B) Gravitational force
7️⃣ C) 300 N/m
8️⃣ B) 4000 N
9️⃣ C) A falling ball
🔟 B) At the lowest point
1️⃣1️⃣ D) 128 J
1️⃣2️⃣ B) It is conserved in all collisions
1️⃣3️⃣ B) Acceleration
1️⃣4️⃣ B) 2 m/s
1️⃣5️⃣ A) Centripetal force
1️⃣6️⃣ C) Potential energy
1️⃣7️⃣ C) 43.3 N
1️⃣8️⃣ D) Both A and C
1️⃣9️⃣ B) Friction
2️⃣0️⃣ C) 50 N