Combined Science Physics Flashcards
6 cards from real GCSE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Combined Science Physics flashcards as text
What is the unit of measurement for electrical resistance?
Answer: Ohms (Ω)
Resistance is measured in ohms (Ω), named after Georg Ohm. Resistance is the opposition to the flow of current in a circuit. It can be calculated using Ohm's Law: R = V ÷ I (resistance = voltage ÷ current).
A force of 200 N is applied to an area of 0.5 m². What is the pressure?
Answer: 400 Pa
Pressure = force ÷ area = 200 ÷ 0.5 = 400 Pa. Pressure is measured in pascals (Pa). A smaller area with the same force creates a greater pressure, which is why sharp objects penetrate more easily.
Which type of electromagnetic wave has the shortest wavelength?
Answer: Gamma rays
Gamma rays have the shortest wavelength and highest frequency in the electromagnetic spectrum. The order from longest to shortest wavelength is: radio, microwave, infrared, visible light, ultraviolet, X-rays, gamma rays.
What is the law of conservation of energy?
Answer: Energy cannot be created or destroyed, only transferred between stores
The law of conservation of energy states that energy cannot be created or destroyed — it can only be transferred from one energy store to another. The total energy in a closed system always remains constant.
A car accelerates from rest to 20 m/s in 5 seconds. What is its acceleration?
Answer: 4 m/s²
Acceleration = change in velocity ÷ time = (20 - 0) ÷ 5 = 4 m/s². Starting 'from rest' means the initial velocity is 0 m/s. Acceleration tells us how quickly the velocity is changing.
What happens to the current in a series circuit when more resistors are added?
Answer: The current decreases
In a series circuit, adding more resistors increases the total resistance. Since the supply voltage stays the same and V = IR, a higher resistance means a lower current flows through the circuit.