Transcript PH Force Assignment 1a. Net force is the combination of all forces acting on an object.

PH Force Assignment
1a. Net force is the combination of all forces
acting on an object. The net force determines
whether an object moves and also in which
direction it moves.
1b.
2a. To calculate the net force, you combine the
opposing forces by subtraction.
2b. Balanced forces cancel and do not change the
object’s motion. Unbalanced forces cause the object’s
motion to change.
2c. The net force is 270N
2a. Static Friction-
The friction that acts on objects
that are not moving.
Sliding friction- occurs when two solid surfaces
slide over each other.
How might you
increase or
decrease sliding
friction?
Rolling Friction- when an object rolls across a surface.
Fluid friction- occurs when a solid object moves through
a fluid.
3a.
Buoyant force- acts in the direction opposite to
the force of gravity, so it makes an object feel
lighter. The less dense an object is, the greater
the buoyant force it experiences.
Archimedes’ principle- states that the buoyant
force acting on a submerged object is equal to
the weight of the volume of fluid displaced by
the object.
3b.
1a. Density equals mass per unit volume.
1b. If the object’s density is greater than that of
water, the object will sink; if the object’s density
is less than that of water, the object will float.
1c. Because water cannot enter these
compartments, the air inside them gives the
canoe a greater volume while adding only
slightly to the canoe’s mass. This makes the
canoe less dense than water even if the material
the canoe is made of is denser than water.
3b.
2a. The buoyant force acts upward on a
submerged object, making the object seem
lighter.
2b. The buoyant force on the object equals the
weight of the fluid displaced by the object.
2c. Because the object floats, the weight of the
displaced water equals the weight of the object,
340 N. The buoyant force on the object equals
its weight, 340 N.
4.
23. The object weighs less in water because the
buoyant force on it in water is opposite to the
force of gravity.
24. The buoyant force is 2.0 N.
25. The volume of water above the dotted line is
equal to the volume of the object. The weight of
the volume of displaced water is equal to the
buoyant force on the object, 2.0 N.