The correct option is this: PHYSICAL CHANGES: BREAKING THE STICKS AND BOILING THE WATER. CHEMICAL CHANGE: LIGHTNING THE FIRE.
In chemistry, a physical change refer to a change in which no new material is formed while a chemical change refers to a change in which a new material is formed. Boiling of water does not change water into another thing, even when the water changes to vapor, it will still turn to water again when it cools down, so boiling is a physical change, so also the breaking of sticks. Lightening a fire on the other hand is a chemical change because a new material is formed and the original material can not be recovered. Putting fire on the sticks will turn the sticks to ashes and the sticks can not be recovered from the ashes, so this is a chemical change.
L = length of the incline = 75 m
θ = angle of incline = 22 deg
h = height of skier at the top of incline = L Sinθ = (75) Sin22 = 28.1 m
μ = Coefficient of friction = 0.090
N = normal force by the surface of incline
mg Cosθ = Component of weight of skier normal to the surface of incline opposite to normal force N
normal force "N" balances the component of weight opposite to it hence we get
N = mg Cosθ
frictional force acting on the skier is given as
f = μN
f = μmg Cosθ
v = speed of skier at the bottom of incline
Using conservation of energy
potential energy at the top of incline = kinetic energy at the bottom + work done by frictional force
mgh = f L + (0.5) m v²
mgh = μmg Cosθ L + (0.5) m v²
gh = μg Cosθ L + (0.5) v²
(9.8 x 28.1) = (0.09 x 9.8 x 75) Cos22 + (0.5) v²
v = 20.7 m/s
Answer:
13.18 m/s
Explanation:
Let the velocity of sports utility car is
-u as it is moving in opposite direction.
mc = 1200 kg, uc = 31.1 m/s
ms = 2830 kg, us = - u = ?
Using conservation of momentum
mc × uc + ms × us = 0
1200 × 31.1 - 2830 × u = 0
u = 13.18 m/s
Answer:
Each layer has its own properties, composition, and characteristics that affects many of the key processes of our planet. They are, in order from the exterior to the interior – the crust, the mantle, the outer core, and the inner core.
Explanation:
Answer: Go to the harbor. When a ship sails off toward the horizon, it doesn't just get smaller and smaller until it's not visible anymore. Instead, the hull seems to sink below the horizon first, then the mast. When ships return from sea, the sequence is reversed: First the mast, then the hull, seem to rise over the horizon.
Climbing to a high point will allow you to be able to see farther if you go higher. If the Earth was flat, you'd be able to see the same distance no matter your elevation
