Worksheet: Force and Pressure

In this worksheet, we will practice defining pressure as the force per unit area and calculating pressures acting on a surface.

Q1:

Why are sharper knives more effective at cutting?

  • AThe smaller contact surface of a sharper knife can react faster with the surface of what is being cut.
  • BThe sharper the knife, the greater the torque on the cutting surface.
  • CSharper knives have smoother surfaces, allowing them to slide into the weak points of what is being cut.
  • DSharper knives have smaller contact areas so, with the same force, this translates to a greater pressure.

Q2:

Why should you roll or belly-crawl rather than walk across a thinly-frozen pond?

  • AThe more of your body rests on the ice, the less you weigh.
  • BActually, you should walk on tip-toe so that your body heat does not melt the ice.
  • CIf you have more contact with the ice, the ice will warm up and expand, becoming more buoyant.
  • DThe greater your contact area with the ice, the lower the pressure and the risk of it breaking.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.