PASCO ME-8569 DENSITY SET - Manual (Page 11)

scientific 7
012-04774A
Experiment #3: Bouyant Force
REQUIRED EQUIPMENT:
Density set
String (SE-8050)
Overflow can (SE-8568)
Beaker for catching water
Graduated cylinder (50 ml)
Triple-beam balance (SE-8708)
PURPOSE:
This experiment measures the buoyant force on an object in
water by using Archimedes’ Principle and by finding the
upward force on the object while it is submerged.
PROCEDURE
I. ARCHIMEDES’ PRINCIPLE
Archimedes’ Principle states that the buoyant force exerted
on an object partially or fully submerged in a fluid will be
equal to the weight of the fluid displaced by the object. To
use this principle to find the buoyant force exerted on each
object, follow these steps:
1. Find the mass of the empty beaker and record this at the
top of Table 3.1. Put the beaker under the overflow can
spout as shown in Figure 1.
MASS OF BEAKER =
Table 3.1: Measurements
OBJECT
MASS OF BEAKER +
WATER
MASS OF
WATER
WEIGHT OF DISPLACED
WATER
AL. CYLINDER
AL. BLOCK
BRASS CYL.
BRASS BLOCK
PLASTIC CYL.
AL. IRREG. SHAPE
BRASS CYL. 1/2
SUBMERGED
Figure 1: Overflow Setup
2. Pour water into the overflow can until it overflows into
the beaker. Allow the water to stop overflowing on its own
and empty the beaker into the sink and return it to its
position under the overflow can spout without jarring the
overflow can.
3. Tie a string to each of the objects.
4. Gently lower the first object into the overflow can until it
is completely submerged. Allow the water to stop overflow-
ing and then find the mass of the beaker with the water in it.
Record this mass in Table 3.1.