Answer: Option A

Answer: Option C

Answer: Option C

Answer: Option D

Answer: Option B As the coil of the DC motor turns, what are the differences in the turning effect?

Answer: Option A

Answers Option C

Answer: Option D

Answer: Option C

Answer: Option D For double mirror question, image of the cat will be along the last real ray that enters into our eyes. We perceive that light travels in a straight line, so our brain will ‘think’ that the image is straight ahead. So in a way, the short cut to the answer is D. But view the video to learn and understand the concept.

Answer: Option A

Answer: Option D We can use Fleming’s Left Hand Rule to determine the direction of the force on the current carrying wire. The real reason is due to the combined magnetic fields of the current carrying wire and magnets (as shown in the diagram). The resultant magnetic field creates an uneven magnetic field around the wire. The direction of the force on the wire is in the direction from strong magnetic field towards the weak magnetic field region.

Answer: Option C

Answer: Option D Think of the lovers analogy. When both currents are in the same direction, it’s like couple in love, so attraction. Likewise, when the currents are in opposite direction, they quarrel, hence repulsion. On the magnitude of the force, always remember for electric force, magnetic force or gravitational force between objects, the forces are equal and opposite, action-reaction pair (Newton’s 3rd Law).

Answer: Option C

Answer: Option D Under free-fall, where there is no air resistance, when you release the ball or throw a ball up, the moment the ball leaves your hand, the only force acting on the ball is its weight and the acceleration is a constant 10 m/s^2 and is downwards, towards the centre of the Earth.

Answer: Option A Heat capacity (C) is the thermal energy transferred to increase the temperature of the substance by 1 oC or 1 K. Specific heat capacity (c) is the thermal energy transferred to increase the temperature of 1 kg of substance by 1 oC or 1 K. The relationship is C = mc i.e. the mass of the beaker is not given as the heat capacity already has taken into account the mass.

Answer: Option B This question can be solved using both Conservation of Energy and Kinematics. Indeed, using COE to solve will be much simpler and straight forward. But do know both methods.

Answer: Option D For this question, I will show you 3 methods to solve. What if the options are not given? The speed and time when the distance is 175 m will be unknown. And based on the basic concepts you learned in speed-time graph, you can form two equations to solve for the unknown speed and time. 1) gradient = acceleration and 2) area under= distance travelled. Some students asked about using the formula v^2 = u^2 + 2as. Though it is not in the syllabus, you can use it i

Answer: Option A View the explanation