float or sink - tech

 FLOATING AND SINKING

Why something floats  Why somethings sinks  Why something semi float FLoating -light , full of air sink-heavy , no air Semi float- when it float and sinks Notes:  Light :buoyant , crew ship Heavy: non buoyant We can tell if its gonna float or not by holding it  Density : the amount of mass something has , relative to its volume. More density more impact  Archimedes Principle - gave us density and buoyancy  BUOYANCY  EXPERIMENTS/ FLOAT OR SINK  Aim purpose: predict the test the buoyancy of objects Equipment: Variety of balls: marbles/large/small Golf ball Table tennis ball Tennis ball Several blocks of material  Different sized wooden block  Different sized plastic block Polystyrene rectangular pieces - two sizes A water bath / two thirds full My partner - kiarah

 RECORDING OF BUOYANCY EXPERIMENT

Name of object	Size - cms L-W-D or diameter	weight  : gms	Composition (what it made out of)	prediction	BUOYANCY RESULT
Golf ball	14.8 cm	46.10 gms	Hard plastic	sink	SINK
Ping pong ball	11.1 cm	2.59 gms	Soft plastic	float	FLOAT
marbel	5 cm	5.15 gms	glass	Semi float	SINK
Big marbel	9.2 cm	22.67 gms	glass	sink	SINK
Tennis ball	20.5 cm	56.81 gms	Rubber	Semi float	SEMI FLOAT
Wood block	99 cm	18.94	wood	Semi float	SEMI FLOAT
Small cube	1 cm	7.95	wood	float	SEMI FLOATS
styrofoam	6.7 cm	0.41 gmas	styrofoam	float	FLOATS
Big cybe	1.9cm	4.59	wood	float	SEMI FLOATS
lego	3 cm	8..49	plastic	Semi float	SEMI FLOATS
block	14 cm	116.96 gms	wood	Semi float	1       SEMI FLOATS

• Before you test each object, accurately measure size and weight , describe the material and predict density Record

• Gently place each object in the water and see it’s behaviour (Sink or Float)