Practice Paper 1A (HL IB Physics)

A parachutist of mass 75 kg is falling vertically through the air at a constant speed of 0.6 m s^–1. 

What is the resultant force on the parachutist? 

The power generated by the nuclear reactions in the core of the reactor is 35 GW.

If the efficiency of the power station is 60%, how much power goes into producing wasted energy?

At the beginning of a wash cycle, a washing machine drum makes its first full revolution from rest in 0.05 seconds.

What is the rotational velocity of the drum after one full revolution? 

A ball of mass 4.0 kg, initially at rest, is acted on by a force F which varies with t.

What is the velocity of the ball after 14 s?

Sankey diagrams are used to represent energy transfers. 

Which Sankey diagram shows the most efficient lightbulb?

A rod is fixed to a pulley. Two 50 N forces are applied to the ends of the rod as shown. The tension in the rope attached to the pulley is T. The system is in equilibrium.

What is the value of the tension in the rope?

A horizontal disc rotates uniformly at a constant angular velocity about a central axis normal to the plane of the disc.

Point X is on a distance 3L from the centre of the disc. Point Y is a distance L from the centre of the disc. Point Y has a linear speed v and a centripetal acceleration a.

What is the linear speed and centripetal acceleration of point X?

Persons A, B & C go to an ice skating rink. Person A sits at the side as an observer. Person B and person C are skating. 

Person B skates away from the cafe at a constant speed of 10 m s⁻¹. Person C skates toward the cafe at a constant speed of 8 m s⁻¹. Persons B and C pass one another in front of Person A. 

What speed is Person C travelling at from Person B's reference frame? 

A sealed cylinder contains water at 10 °C and ice at 0 °C. The system has been thermally isolated from the surroundings. The ice and the water reach thermal equilibrium.

What happens to the total internal energy of the system in order for equilibrium to be reached?

An ideal gas in a simple engine begins in state X. It then undergoes a cyclic process with 4 stages.

Stage 1: The gas is isothermally compressed

Stage 2: The gas gains thermal energy without doing any work

Stage 3: The gas does work isobarically

Stage 4: The gas expands adiabatically

Which diagram correctly shows this cyclic process?

A refrigerator in its surroundings does work and freezes a small amount of liquid water. Which row of the table is correct?

The black body temperature of Venus is 90% of the black body temperature of Earth.

Which of the following correctly shows the ratio:

A black body has absolute temperature T and surface area A. The total power radiated by the body is P. What is the value of power if the surface area is reduced to one third of A, and the temperature increased to three times T?

A power cable X has resistance R and carries current I. A second cable Y has resistance 2R and carries current .

What is the ratio ?

Two resistors are connected to a cell.

Assuming both resistors are made from wires of the same length, which graph shows how the potential V varies along the line XY?

A mass of 5 × 10⁻³ kg of hydrogen is split between two gas bottles Y and Z. Y and Z are connected by a tube that has a negligible volume compared with the volume of each bottle. 

Initially the valve X is closed and gas bottle Y has a volume 4V and contains hydrogen at a pressure p. Gas bottle Z has a volume V and contains Hydrogen at a pressure of 3p. Y and Z are initially at the same temperature. 

X is now opened.

What is the new gas pressure assuming there is no change in temperature?

The star Deneb emits EM waves of wavelengths 500 µm, 5 µm, 0.5 µm and 0.005 µm.

Which row correctly identifies the areas of the EM spectrum to which these wavelengths belong?

A pendulum oscillating with simple harmonic motion has an amplitude and a maximum kinetic energy E_k.

What is the potential energy of the system when the pendulum bob is at a distance 0.4 from its maximum displacement?

A particle, P, oscillates on the line XZ about its equilibrium point Y, in simple harmonic motion.

At the point shown, which statement could be correct about the motion of the particle?

A simple pendulum and a mass-spring system are set up such that the periods of the oscillations are equal. The mass of the pendulum and the mass-spring system are initially identical. The set-up is repeated, but this time the masses of both systems are reduced to three quarters of their original mass.

What is the ratio of the time period of the pendulum to the time period of the mass-spring system after the masses have been changed?

White light is diffracted through a single slit.

Which row in the table indicates the correct positions of red (R), violet (V) and white (W) light on the intensity pattern seen on a screen?  

A student is investigating the interference of waves. They set up coherent waves produced at points S and T and travel outwards in all directions.

The line XY is halfway between S and T and perpendicular to the joining line S and T. The distance XY is much greater than the distance ST.

Which line or lines would an interference pattern be seen along?

Point charges, each of magnitude Q are placed at three corners of a square as shown in the diagram.

What is the direction of the resultant electric field at the corner with no charge?

A mass at point P gives rise to a gravitational field strength g at point X as shown.

An identical mass is placed at point Q as shown.

What is the resultant gravitational field strength at X in this new situation?

A charged particle in an electric field will experience a force on it that will cause it to move. The three particles X, Y and Z are experiencing a force which deflects their motion as shown. What three particles could X, Y and Z be?

The diagram shows equipotential lines around two sources. 

The possible sources of the field are:

1. two equal point charges of the opposite sign
2. two equal point charges of the same sign
3. two equal point masses

What are the only possible sources for the equipotential lines? 

The inverse square law means that halving the radius of a planet results in quadrupling the gravitational field strength at its surface.

The centres of two planets are separated by a distance R. The gravitational force between the two planets is F. What will the force between the planets be when their separation increases to 4R?

Two circular coils, J and K, share a common axis and are parallel to each other. A constant direct current passes through coil J.

Coil K is moved towards coil J and then moved back to its original position. 

As coil K moves, what is the direction of the current induced in coil K relative to the current in coil J?

Two objects X and Y of equal mass, m and distance, D apart move with a constant speed v in circular orbit about their common centre of mass CM. X has a charge of +6.0 nC and Y has a charge of –6.0 nC.

Which graphs shows the electric potential, V and gravitational potential, φ,  against position along the straight-line joining X and Y?

Two points charges of +4Q and –Q are placed 150 mm apart.

 Which of the following graphs shows the variation of the potential V against the distance x along the line joining the two point charges?

A straight wire PQ carrying a constant current I is placed perpendicularly to a uniform magnetic field, as represented by the dotted line in the diagram below.

The current-carrying wire is then rotated anti-clockwise through an angle θ about an axis perpendicular to the plane of the diagram.

Which of the following graphs shows how the magnitude of the magnetic force F on the wire varies with θ in the rangeradians?

Tau Ceti is one of the closest stars to the Sun. Tau Ceti has a surface temperature of 5300 K and a luminosity of 0.55 L_Sun, where L_Sun is the luminosity of the Sun.

Which of the following is the correct description of Tau Ceti?

According to the Bohr model for hydrogen, visible light is emitted when electrons transition to the energy state n = 2 from higher excited states. 

The dotted line in the diagram represents a transition from n = 3 to n = 2 in the spectrum of hydrogen. 

Which of the following diagrams could represent the visible light emission spectrum of hydrogen? 

In a Compton scattering event, incident X-rays have a wavelength of 0.0200 nm and scattered X-rays are found to have a wavelength of 0.0225 nm.

What is the kinetic energy of the recoiled electron and the angle of the scattered X-ray photon?

In a nuclear reactor, a self-sustained chain reaction is possible because:

I.    More neutrons are released in each fission reaction.

II.   Every neutron released in a fission reaction immediately initiates a further fission reaction.

III.  The fast neutrons are slowed down by the moderator.

Which statements are correct?

A pure sample of a radioactive nuclide undergoes a decay resulting in a stable daughter nuclide. What fraction of the sample is made up of the daughter nuclide after five half-lives?

Which of the following statements about stars in positions P, Q, R and S is correct?

Which expression evaluates the de Broglie wavelength of an electron of mass m and charge e in the n = 2 state of hydrogen? 

A vacuum photocell is connected in series with a power supply, a variable resistor, and a sensitive ammeter. A voltmeter is connected in parallel across the photocell.

Monochromatic light of frequency f illuminates the cathode, which has a threshold frequency f₀. Photoelectrons are emitted and collected by the anode. A photocurrent is measured by the ammeter.

The potential difference across the photocell, V, is increased until the ammeter reads zero. 

Which of the equations below does not correctly relate the potential V at which the current decreases to zero to the threshold frequency f₀ and frequency f?