IB myp 4-5 physics – Practice Questions- All Topics
Topic :Forces and energy-Forces and effect of forces
Topic :Forces and energy– Weightage : 21 %
All Questions for Topic : Types of forces, forces in circular motion, momentum \& impulse
Some musical instruments, such as the guitar, make sounds by vibrating strings.
Question (2 mark)
Calculate the force of tension in the wire if the hanging mass is $300 \mathrm{~g}$. You should assume that gravitational field strength is $10 \mathrm{~N} \mathrm{~kg}^{-1}$.
▶️Answer/Explanation
Ans:
force of tension in the wire $=$ weight of the hanging mass
force of tension in the wire $=\mathrm{mg}$
force of tension in the wire $=0.3 \times 10$
force of tension in the wire $=3 \mathrm{~N}$
Question (3 marks)
The Shinkansen, commonly known as a bullet train, is a network of high-speed magnetic levitation trains in Japan. The Paragraph below explores how the trains were redesigned to minimize the loud booms produced when the trains entered a tunnel.
Japanese bullet trains were first designed in 1964. These trains use magnetic levitation. The repelling force between magnets is used to raise the train above the tracks. This reduces friction and allows the train to travel at very high speeds.
When in a tunnel, the fast speed and the bullet shape caused a layer of air to build up in front of a train. This caused a loud booming sound when the train exited the tunnel.
Scientists noticed that kingfisher birds did not disturb water when they dived into it due to the shape of their beaks. They redesigned the nose of the train by modelling it on a kingfisher’s beak.
The redesigned train cut through the air and reduced the build-up of layers of air in tunnels. This reduced the loud booming sound and increased the train’s efficiency.
Question a (1 mark)
Select the unit for measuring force.
▶️Answer/Explanation
Ans:
Newton
Question b (2 marks)
The diagram below shows the forces acting on the 1964 train traveling at a constant maximum speed of $220 \mathrm{~km} \mathrm{~h}^{-1}$.
Label the forces in the diagram.
▶️Answer/Explanation
Ans: