October 22, 2012 Students will learn about mass, length and volume. The bowling ball and the balloon take up the same amount of space ( have equal volumes ) Do equal volumes of different substances always have the same mass? on DO NOW • 1. What tool is used to measure length? • 2. What tool is used to measure mass? • 3. What tool is used to measure temperature? Length • Definition • Distance between two points Length • Tool • Ruler or meter stick Length • Label units • Centimeter (cm) Length • Tips • Line object up at zero mark • Measure with decimals (no fractions) • Be accurate • Label your answer Example • What is the length of the object at left? Example • What is the length of the object at left? Example • What is the length of the object at left? Mass • Definition • Amount of matter in an object Mass • Tool • Triple beam balance Mass • Label units • Grams (g) • Using a tbb • 1. Zero the balance (all masses left) • Using a tbb • 2. Move 100 g mass first- until balance tips, then slide mass one spot left • Using a tbb • 3. Move 10 g mass next until balance tips, then slide mass one spot left • Using a tbb • 4. Move 1 g mass last until balance tips, then slide mass one spot left • Using a tbb • 5. Add up all three masses to find the total mass Mass • Tips • Be accurate • Use decimals, no fractions • Label your answer correctly Triple Beam Balance Used to Measure Mass Parts of the Triple Beam Balance PAN ZERO/ TARE KNOB MOVEABLE MASSES BEAMS BALANCE POINT BASE A Closer Look at the Beams 10 gram beam 100 gram beam 1 gram beam Converting g to mg 1 g =1,000mg (1 gram = 1,000 milligrams) When changing grams to milligrams, the decimal is moved 3 places to the RIGHT Example: 50.0 grams=50,000.0 milligrams Practice reading the mass on the Beams 1. If the middle beam is on 400g, the back beam is on 50g and the front beam is on 7g, what is the total mass in grams? Mg? Kg? 2. If the middle beam is on 200g, the back beam is on 20g and the front beam is on 5.2g, what is the total mass in grams? Mg? Kg? 3. If the middle beam is on 500g, the back beam is on 10g and the front beam is on 1.2g, what is the total mass in grams? Mg? Kg? Using a Triple Beam Balance 1. Wipe off the pan Using a Triple Beam Balance 2. Move all of the weight to zero (the far left) Using a Triple Beam Balance 3. Adjust the tare knob ( or adjustment knob) until the pointer lines up with the zero mark Tare knob or adjustment knob Using a Triple Beam Balance 4. Carefully place the object on the pan. Leaving the weights at zero for now. Using a Triple Beam Balance 5. Move the weight on the bars until the pointer lines up with the zero mark. *For large or heavy objects start with the large weight that moves in 100 gram increments * For small and lighter objects start with the smaller weights that move in 1 gram or 10 gram increments Using a Triple Beam Balance 5. Using a Triple Beam Balance 6. After finding which heaviest weight on the 100 gram bar still allows the pointer to point above the zero mark, start adding smaller amounts from the other bars. Do this first with the weights on the 10 gram bar then the one gram bar until the pointer is lined up with the zero line NOTE: The one gram bar is very sensitive. Touch it very carefully and move the weight slowly Using a Triple Beam Balance 6A Using a Triple Beam Balance 6B REVIEW: Using a Triple Beam Balance 1. Wipe off the pan 2. Move all of the weights to zero 3. Adjust the tare knob( also called the adjustment knob) until the pointer lines up with the zero mark 4. Carefully put the object on the pan Using a Triple Beam Balance 5. Move the weight on the bars until the pointer lines up with the zero mark. *For large or heavy objects start with the large weight that moves in 100 gram increments * For small and lighter objects start with the smaller weights that move in 1 gram or 10 gram increments Using a Triple Beam Balance 6. After finding which heaviest weight on the 100 gram bar still allows the pointer to point above the zero mark, start adding smaller amounts from the other bars. Do this first with the weights on the 10 gram bar then the one gram bar until the pointer is lined up with the zero line NOTE: The one gram bar is very sensitive. Touch it very carefully and move the weight slowly Calculating the Volume of a Regular Object • Calculating the volume of a regular object is easy. • Just multiply Length X Width X Height Width Length Height Calculating the Volume of a Cubic Object • For instance, if you have a cube that is 4 centimeters long, 4 centimeters wide and 4 centimeters high you would multiply 4cm X 4cm X 4cm = 64 cubic centimeters