Single correct · +4 / −1
The SI unit of pressure is:
- (a) N/m
- (b) N/m²
- (c) N·m
- (d) Pa·s
Answer and solution
Answer (b) N/m²
Solution
Physics sir · 3 steps
Start from the definition: pressure is force spread over an area, so divide newtons by square metres.
- Definition. Pressure is the normal force acting on a surface divided by the area of that surface.
P = F/A ⇒ N/m² = Pa
- Check the others. N/m is force per length, the unit of surface tension or spring constant. N m is force times distance, the unit of work or torque. Pa s is the unit of viscosity.
- So. The SI unit of pressure is N/m², named the pascal (Pa). The answer is (b).
The idea to keep. To get the unit of any quantity, write its defining formula and replace each quantity with its unit. Area brings in m², never just m.
Answer from the NTA final answer key. Solution by PrepWiser.