G12 Physics test 1

A micrometer is used to measure the diameter of a uniform wire.

What is done to obtain an accurate answer ?

The mass of a paper-clip is 0.50 g and the density of its material is 8.0 g/cm³. The total volume of number of clips is 20 cm³.    How many paper-clips are there?

Which pair of quantities includes one scalar and one vector?

What affects the stability of an object?

Forces of 25 N and 40 N act on an object in the directions shown

Which arrow shows the direction of the resultant force on the object?

Objects of different weights are placed on a rigid, horizontal surface. Which row shows the correct pressure acting on the surface?

A block of metal is taken from the Earth to the Moon. Which property of the block changes?

A car of mass 1500 kg is towing a trailer of mass 1100 kg along a level road. The acceleration of the car is 1.30 m/s². Ignoring friction and air resistance, what is the driving force on the car?

Paper is sold in packets labelled 80 g / m². This means that a sheet of paper of area 10 000 cm² has a mass of 80 g. The thickness of each sheet is 0.11 mm.

What is the density of the paper?

Which chair is the least stable if the child moves ?

The diagram shows a simple manometer that contains a liquid

Side X is connected to a gas supply of pressure R. Side Y is open to the atmosphere at pressure S.

Which pressure is the length h used to measure?

A student uses a newton meter to pull an object horizontally along rough ground. The student multiplies the newton meter reading by the distance moved by the object. What does this calculation give?

The diagram shows the energy transfer through a machine.

The machine is 50% efficient.

Which equation is correct

A builder carrying six bricks climbs a ladder. Each brick weighs 25 N and the builder climbs a vertical distance of 4.0 m in 8.0 s.

What is the average power used to raise the bricks

 A copper rod is heated at one end. Which statement describes how heat transfer occurs in the copper?

Less heat is needed to raise the temperature of 1 kg of copper by 1 °C than is needed to raise the temperature of 1 kg of water by 1 °C. Which statement explains this?

A centimetre scale is fixed next to an unmarked mercury-in-glass thermometer. The ice point and the steam point are marked.

What is the temperature shown on the thermometer?

How is heat conducted in a metal?

1. A strip is made from two metals joined together. The diagrams show the strip at room temperature and after it has been cooled.

The change in shape occurs because

Two identical metal plates are painted, one matt (dull) white and the other matt black. These are placed at equal distances from a radiant heater as shown. The heater is turned on for five minutes.

Which metal plate absorbs more energy and which plate emits more energy in this time?

A wave of frequency 13 000 Hz travels 1300 m in 4.0 s.

What is the wavelength of the wave?

The diagram shows light travelling through a medium. The light reaches the boundary with a vacuum as shown. The light emerges travelling along the surface.

What is the refractive index of the medium?

The diagram shows an object on the principal axis of a converging (convex) lens. A principal focus of the lens is at F.

Where is the image formed by the lens?

Light is incident on one face of a glass block at an angle of incidence of 40°. The glass block is in air. The refractive index of the glass is 1.46.

What is the angle of refraction inside the glass block?

A lamp connected to a 12 V supply converts energy at a rate of 36 W. How much energy will be converted in 10 s?

The diagram shows a 12 V d.c. power supply connected across a coil with a metal core.

The core becomes a magnet when the current is switched on. It remains a magnet after the current is switched off. From which metal is the core made?

A 12 V battery is connected across a parallel arrangement of two resistors.

What is the reading on the ammeter?

A transformer connected to a 240 V mains supply is used to light a 24 W lamp.

The input current to the transformer is 0.11 A and the input voltage is 240 V. The useful output power of the transformer is 24 W.  What is the efficiency of the transformer?

A bar magnet is pushed into one end of a long coil connected to a sensitive meter.

Which of the following affects the magnitude of the deflection of the meter?

A rectangular coil is placed between the poles of a magnet. A current passes through the coil, as shown.

What happens to the coil?

The energy emitted by the Sun is released when the nuclei of an element fuse together. Which nuclei, when fusing together, release most of the energy in the Sun?

A sample of wood contains 9.0 × 10¹⁶ nuclei of carbon-14. The nuclei undergo radioactive decay with a half-life of 5600 years. How many carbon-14 nuclei remain in this sample after 16 800 years?

How many nucleons are in one neutral atom of the krypton isotope Kr? 8436