WA1 Practice Paper: Weighted Assessment 1 — question paper

Section A: Multiple-choice questions[10 marks]

Answer all questions. For each question, write the letter (A, B, C or D) of the correct answer in the brackets provided.

1. 1

   A textbook lies still on a table. Which pair of forces on the book is balanced?

   1. Aits weight and the upward push from the table
   2. Bfriction and air resistance only
   3. Conly its weight
   4. Dthe push of the book on the table and its weight
   ( )
2. 2

   Heat travels along a metal spoon standing in hot soup, but the spoon itself does not move. This transfer is

   1. Aconvection
   2. Bradiation through a vacuum
   3. Cconduction
   4. Devaporation
   ( )
3. 3

   A student pushes a trolley. Which force acts against the motion of the wheels on the floor?

   1. Aweight
   2. Bfriction
   3. Cthe normal contact force
   4. Dupthrust
   ( )
4. 4

   Two identical cans of water sit in the sun. One is painted matt black and one is shiny white. Which can warms faster, and why?

   1. Athe white can, because shiny surfaces are better absorbers
   2. Bboth cans warm at the same rate
   3. Cthe white can, because white surfaces emit more radiation
   4. Dthe black can, because matt black surfaces absorb radiation better
   ( )
5. 5

   The same downward force is applied by a drawing pin and by a fingertip. Why does the pin pierce paper more easily?

   1. Aits tip has a smaller area, so the pressure is higher
   2. Bits tip has a larger area, so the pressure is higher
   3. Cthe pin has a larger weight
   4. Dthe pin removes friction
   ( )
6. 6

   Convection can transfer heat in

   1. Aa solid metal bar only
   2. Ba vacuum only
   3. Ca liquid or a gas
   4. Dany solid
   ( )
7. 7

   A student squashes a lump of plasticine and it stays flattened. Which effect of a force is this?

   1. Achanging the speed of the plasticine
   2. Bchanging the shape of the plasticine
   3. Cchanging only its temperature
   4. Dremoving its weight
   ( )
8. 8

   Why are cooking pots often made of metal, with a plastic handle?

   1. Ametal is a poor conductor and plastic is a good conductor
   2. Bboth metal and plastic are poor conductors
   3. Cmetal stops heat reaching the food
   4. Dmetal conducts heat to the food, and plastic keeps the handle cooler
   ( )
9. 9

   A metal jar lid is too tight to turn. Running hot water over the lid makes it easier to open. Why?

   1. Athe metal lid expands more than the glass jar
   2. Bthe metal lid contracts
   3. Chot water reduces the weight of the lid
   4. Dthe glass expands more than the metal
   ( )
10. 10

    The walls of a vacuum flask are silvered. What does the silvering reduce?

    1. Aconduction through the glass
    2. Bconvection in the liquid
    3. Cheat transfer by radiation
    4. Dthe weight of the flask
    ( )

Section B: Structured questions[20 marks]

Answer all questions in the spaces provided. Show your working for calculations.

1. 1

   A 4.0 N book rests on a desk. A student then pushes it with a horizontal force of 6.0 N. Friction is 2.0 N.

   1. (a)

      State the size of the upward force from the desk on the book before it is pushed. Explain your answer.

      [2]
   2. (b)

      Calculate the resultant horizontal force when the student pushes the book.

      resultant force =N[2]
   3. (c)

      State what happens to the speed of the book because of this resultant force.

      [1]
2. 2

   A student compares two bags of the same weight. One strap is narrow and one strap is wide.

   1. (a)

      State which strap presses more painfully into the shoulder.

      [1]
   2. (b)

      Explain your answer to (a). Use the idea of pressure.

      [2]
   3. (c)

      A drawing pin is pushed into a noticeboard with a force of 12 N. The tip has an area of 0.0002 m². Calculate the pressure at the tip.

      pressure =N/m²[2]
3. 3

   A metal rod has one end in a Bunsen flame. A drop of wax is placed on the other end.

   1. (a)

      Name the process that transfers heat along the rod to the wax.

      [1]
   2. (b)

      Describe how the particles of the metal pass the energy along the rod.

      [2]
   3. (c)

      The rod is replaced by a glass rod of the same size. State what happens to the time taken for the wax to melt, and why.

      [2]
4. 4

   A room is heated by a heater standing on the floor.

   1. (a)

      Describe how convection moves warm air around the room.

      [2]
   2. (b)

      The heater also gives out infra-red radiation. State one surface that would absorb this radiation well.

      [1]
   3. (c)

      Explain why a vacuum between the walls of a flask reduces heat loss, while silvering the walls reduces a different kind of heat loss.

      [2]