iGCSE Physics (0625) 1.8 Pressure-Exam Style Questions- New Syllabus
▶️ Answer/Explanation
Detailed solution:
Pressure is defined as the force applied per unit area, expressed by the formula p= A F .
In this scenario, the force F is the weight of the skier, which is 550 N.
The total contact area A provided is 0.015 m 2 .
Substituting these values into the equation: p= 0.015 550 .
Performing the calculation gives p≈36666.67 N/m 2 .
Rounding to two significant figures as per the options, we get 37000 N/m 2 .
Therefore, the correct pressure exerted is represented by Option D.
▶️ Answer/Explanation
Detailed solution:
Pressure is defined as the force applied per unit area, expressed by the formula $p = \frac{F}{A}$.
According to this relationship, pressure is inversely proportional to the surface area $A$ for a constant force $F$.
By sharpening a knife to a very small surface area at the edge, the pressure exerted becomes significantly higher.
This high pressure allows the knife to cut through materials much more easily with minimal effort.
Options B, C, and D are incorrect as area does not affect the intrinsic density, chemical rusting, or magnetism of the steel.
▶️ Answer/Explanation
Detailed solution:
Pressure is defined as the force acting per unit area, expressed by the formula $p = \frac{F}{A}$.
In the SI system, the unit for force ($F$) is the Newton ($N$) and the unit for area ($A$) is the square metre ($m^{2}$).
Substituting these units into the formula gives $N/m^{2}$, which is also known as the Pascal ($Pa$).
Option B ($kg/m^{3}$) represents density, while Option C ($Nm$) represents the moment of a force or work done.
Therefore, $N/m^{2}$ is the only correct unit for pressure among the choices provided.