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Which statement best describes the difference between distance and displacement?

Select one option

Distance is a vector quantity, while displacement is a scalar quantity.

Displacement is always greater than or equal to distance.

Displacement is the straight-line distance and direction from start to end; distance is the total path length traveled.

Distance can be negative, but displacement cannot.

A car travels 100 meters in 40 seconds. What is its average speed?

Select one option

0.4 m/s

2.5 m/s

4.0 m/s

400 m/s

A projectile is launched at an angle above the horizontal. At the very peak of its trajectory, what are the characteristics of its velocity?

Select one option

Its vertical velocity is maximum, and its horizontal velocity is zero.

Its vertical velocity is zero, and its horizontal velocity is constant and non-zero.

Both its vertical and horizontal velocities are zero.

Both its vertical and horizontal velocities are at their maximum values.

A ball is dropped from rest from a height. Neglecting air resistance, what is its speed after 0.5 seconds? (Use $g = 9.8 \text{ m/s}^2$ )

Select one option

0.5 m/s

4.9 m/s

9.8 m/s

19.6 m/s

Newton's First Law of Motion describes:

Select one option

The relationship between force, mass, and acceleration.

The principle of action-reaction pairs.

The conservation of energy in a system.

An object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

A 2 kg object experiences an acceleration of $1.5 \text{ m/s}^2$ . What is the net force acting on the object?

Select one option

0.75 N

1.5 N

3 N

4 N

Which statement about friction is true?

Select one option

Friction always opposes the direction of motion.

Friction depends on the contact area between surfaces.

Static friction is generally greater than kinetic friction.

Friction is independent of the normal force.

According to Newton's Third Law of Motion, when a car accelerates forward, the action-reaction pair of forces involves:

Select one option

The engine pushing the car forward, and air resistance pushing it backward.

The car exerts a force on the road, and the road exerts an equal and opposite force on the car.

The car pushes on the air, and the air pushes on the car.

The car pushes on the passenger, and the passenger pushes back on the car.

The Work-Energy Theorem states that:

Select one option

Work done is always equal to the force applied multiplied by the distance moved.

Energy can neither be created nor destroyed, only transferred or transformed.

The net work done on an object equals the change in its kinetic energy.

The total mechanical energy of a system remains constant if only conservative forces do work.

10.

A 4 kg object is moving at a speed of $5 \text{ m/s}$ . What is its kinetic energy?

Select one option

10 J

20 J

25 J

50 J

11.

In a system where mechanical energy is conserved, which of the following is true?

Select one option

Kinetic energy is always equal to potential energy.

Work done by non-conservative forces is always zero.

The total mechanical energy remains constant if only conservative forces (like gravity) are doing work.

The system is isolated from all external forces.

12.

A motor lifts a 20 kg mass through a vertical height of 10 meters in 5 seconds. What is the average power output of the motor? (Use $g = 9.8 \text{ m/s}^2$ )

Select one option

20 W

39.2 W

40 W

100 W

13.

What is the primary difference between heat and temperature?

Select one option

Heat is a form of energy, while temperature is a property of matter.

Temperature can be measured in joules, while heat is measured in degrees Celsius.

Heat is the transfer of thermal energy, while temperature is a measure of the average kinetic energy of particles.

Temperature is always higher than heat in a given system.

14.

Specific heat capacity is defined as:

Select one option

The total energy contained within a substance.

The amount of heat required to change the phase of 1 kg of a substance.

The rate at which heat is transferred through a material.

The amount of heat required to raise the temperature of 1 kg of a substance by 1 degree Celsius.

15.

The First Law of Thermodynamics is a statement of:

Select one option

The spontaneous flow of heat from hotter to colder objects.

The efficiency limits of heat engines.

Energy is conserved; the change in internal energy of a system equals the heat added to the system minus the work done by the system.

The relationship between pressure, volume, and temperature for an ideal gas.

Diagram for Question 16

16.

A 0.5 kg block is placed on a ramp inclined at an angle of $30^\circ$ to the horizontal. The coefficient of kinetic friction between the block and the ramp is 0.2. The block slides down the ramp. (Use $g = 9.8 \text{ m/s}^2$ )

a) Draw a clear free-body diagram for the block, labeling all forces acting on it. b) Calculate the magnitude of the normal force acting on the block. c) Calculate the magnitude of the kinetic friction force acting on the block. d) Calculate the acceleration of the block down the ramp.

17.

A roller coaster car of mass 500 kg starts at rest at point A, which is at a height of 20 meters. It then travels down a track to point B, which is at a height of 5 meters, and then continues to point C. Assume no friction or air resistance, and use $g = 9.8 \text{ m/s}^2$ .

a) If the car starts with a speed of $10 \text{ m/s}$ at point A, what is its speed when it reaches point B? b) If the car has a speed of $15 \text{ m/s}$ at point C, what is the height of point C? c) Explain why the total mechanical energy of the roller coaster car is conserved throughout its motion from A to C, neglecting friction and air resistance.

18.

A 1000 W electric heater is used to heat 0.5 kg of water from $20^\circ C$ to its boiling point ( $100^\circ C$ ). Given: Specific heat capacity of water, $c_{water} = 4186 \text{ J/kg\cdot{}^\circ C}$ . Latent heat of vaporization of water, $L_v = 2.26 \times 10^6 \text{ J/kg}$ .

a) Calculate the amount of heat energy required to raise the temperature of the water to its boiling point. b) After reaching the boiling point, the heater continues to operate. How long will it take for half of the water to turn into steam (vaporize)? State your answer in seconds.

19.

You are performing an experiment to determine the specific heat capacity of an unknown metal using a calorimetry method. You heat a 50.0 g sample of the metal to $95.0^\circ C$ in boiling water. You then quickly transfer it to a calorimeter containing 200.0 g of water initially at $20.0^\circ C$ . The final equilibrium temperature of the water and metal is $28.5^\circ C$ . Assume the specific heat capacity of water is $4186 \text{ J/kg\cdot{}^\circ C}$ and the calorimeter itself absorbs negligible heat.

a) Calculate the heat energy gained by the water. Calculate the heat energy lost by the metal. Calculate the experimental specific heat capacity of the unknown metal.

b) Based on your calculated specific heat capacity, what can you conclude about the unknown metal? Compare your value to known specific heats of common metals (e.g., Copper: ~ $385 \text{ J/kg\cdot{}^\circ C}$ , Aluminum: ~ $900 \text{ J/kg\cdot{}^\circ C}$ , Iron: ~ $450 \text{ J/kg\cdot{}^\circ C}$ , Lead: ~ $130 \text{ J/kg\cdot{}^\circ C}$ ). Is your value unusually high or low?

c) Discuss two potential sources of experimental error in this setup and suggest one specific improvement for each to obtain a more accurate result.

d) If your calculated specific heat capacity differs from the true value of the metal, explain how the principle of energy conservation relates to this discrepancy and what factors might account for it.