Unbalanced forces cause changes in velocity. As a basis for understanding this concept:
a. Students know
a force has both direction and magnitude.
Activity: Making an
Impact , Read 10:1 pp.374-377 The Nature of Force,
notes:What
is Force?, Inertia,
Friction,
gravity
b. Students know
when an object is subject to two or more forces at once, the result is
the cumulative effect of all the forces. Read
10:1 pp.374-377 The Nature of Force,
notes:What
is Force?, 10:2 pp 380-388
Friction, Gravity and Elastic Forces, Centripetal Forces, Projectile
Motion, Forces on an airplane
c. Students know
when the forces on an object are balanced, the motion of the object does
not change. Read 10:1
pp.374-377 The Nature of Force,
notes:What
is Force?,
Summary
on Newtons Laws
d. Students know how
to identify separately the two or more forces that are acting on a single
static object, including gravity, elastic forces due to tension or compression
in matter, and friction. Read
10:2 pp. Friction, Gravity, Elastic Force,
Read 10:2 pp 380-388 Friction, Gravity and Elastic Forces, Notes:Multiple
forces acting on an object. Centripetal Forces, Projectile
Motion, Forces on an airplane Lab Activites: Multiple
forces acting on an object
e. Students know that when the forces on an object are unbalanced, the object will change its velocity (that is, it will speed up, slow down, or change direction). Read 10:1 pp.374-377 The Nature of Force, notes:What is Force?, Solve the Math Practice Problems. p. 392
f. Students know the greater the mass of an object, the more force is needed to achieve the same rate of change in motion. Read 10:1 pp.374-377 The Nature of Force, notes:What is Force?, Solve the Math Practice Problems. p. 392
g. Students know
the role of gravity in forming and maintaining the shapes of planets, stars
and the solar system. Read
10:1 pp.374-377 The Nature of Force,
notes:What
is Force?, Chapter 10 Section
5 pp402-405. Notes:Multiple
forces acting on an object. Centripetal Forces, Projectile
Motion, Forces on an airplane