p5 forces

• the length of the arrow shows the magnitude , the direction of the arrow shows the direction of vector quantity
• non contact forces - gravitational, electrostatic, magnetic, force
• weight = mass × gravitational field strength
• The resultant force has the same effect as all the original forces acting together. If forces are balanced the resultant force is zero.
• work done = force × distance
• work done against the frictional forces acting on an object causes a rise in the temperature of the object.
• force = spring constant × extension
• the extension of an elastic object is directly proportional to the force applied
• if an object is balanced, the total clockwise moment about a pivot equals the total anticlockwise moment about that pivot.
• the pressure in fluids causes a force normal (at right

  angles) to any surface.
• pressure = force/area