4:chemical properties can only be observed when a substance changes into another substance.
5: physical properties such as color and shape are easy to observe
6: in a chemical change an altered substance forms
7: cooking or baking food will result in a chemical change
8: a melting ice cube is a physical change
9: the rusting of iron is a chemical change
10: water boiling is a scientific physical change
overuse of a muscle Answer:
Explanation:
Answer
given,
given,
small cube side = 10 cm
larger cube side = 12 cm
density of steel = 7 g/cm³
density of aluminium = 2.7 g/cm³
density of the water (ρ₁)= 1 g/cm³
Cube A and B made of steel
buoyant force of Cube A
B₁ = ρ₁ V g = 1 x 10 x 10 x 10 x g= 1000 g
for cube B
B₂ = ρ₁ V g = 1 x 12 x 12 x 12 x g= 1728 g
buoyant force of Cube C
B₃ = ρ₁ V g = 1 x 10 x 10 x 10 x g= 1000 g
for cube D
B₄ = ρ₁ V g = 1 x 12 x 12 x 12 x g= 1728 g
buoyant force acting on the cube depends on the density of the fluid
hence,
B₂ = B₄ > B₁ = B₃
===> Distance fallen from rest in free fall =
(1/2) (acceleration) (time²)
(122.5 m) = (1/2) (9.8 m/s²) (time²)
Divide each side by (4.9 m/s²): (122.5 m / 4.9 m/s²) = time²
(122.5/4.9) s² = time²
Take the square root of each side: 5.0 seconds
===> (Accelerating at 9.8 m/s², he will be dropping at
(9.8 m/s²) x (5.0 s) = 49 m/s
when he goes 'splat'. We'll need this number for the last part.)
===> With no air resistance, the horizontal component of velocity
doesn't change.
Horizontal distance = (10 m/s) x (5.0 s) = 50 meters .
===> Impact velocity = (10 m/s horizontally) + (49 m/s vertically)
= √(10² + 49²) = 50.01 m/s arctan(10/49)
= 50.01 m/s at 11.5° from straight down,
away from the base of the cliff.
The two letters are B and A, in that order.
