Complete question:
A casting with a mass of 500 kg rests on a surface with a slope of 20° to the horizontal. The coefficient of friction is 0.25.
Calculate;
(a) the component of the weight of the object perpendicular to the surface
(b) the component of the weight of the object parallel to the surface
Answer:
(a) the component of the weight of the object perpendicular to the surface is 4,604.5 N
(b) the component of the weight of the object parallel to the surface is 1,675.9 N
Explanation:
Given;
mass of the casting, m = 500 kg
angle of inclination of the casting, θ = 20⁰
the coefficient of friction, k = 0.25
(a) the component of the weight of the object perpendicular to the surface;
F⊥ = mgcosθ
F⊥ = 500 x 9.8 x cos20
F⊥ = 4,604.5 N
(b) the component of the weight of the object parallel to the surface
F|| = mgsinθ
F|| = 500 x 9.8 x sin(20)
F|| = 1,675.9 N
Answer: C. Reward Jamal for not interrupting her during a phone call
Explanation: Operant conditioning is a learning process which is used to adjust or shape the nature or strength of an child's attitude or behavior either through reinforcement or punishment. Operant conditioning is used to explain changes which occur in the strength or ability to repeat a certain behavior due to the consequences of such behavior or action. Reinforcement increases the strength of a behavior and increases the likelihood of future occurrences while punishment decreases the strength of an action and decreases the likelihood of future occurrences.
In the scenario above, If Jamal is rewarded for not interrupting a phone call, the behavior will be strengthened and increases the likelihood of future occurrence, that is, not interrupting phone calls in the future.
Answer:
There are four main stages in the water cycle. They are evaporation, condensation, precipitation and collection. Let's look at each of these stages.
Evaporation: This is when warmth from the sun causes water from oceans, lakes, streams, ice and soils to rise into the air and turn into water vapour (gas). Water vapour droplets join together to make clouds!
Condensation: This is when water vapour in the air cools down and turns back into liquid water.
Precipitation: This is when water (in the form of rain, snow, hail or sleet) falls from clouds in the sky.
Collection: This is when water that falls from the clouds as rain, snow, hail or sleet, collects in the oceans, rivers, lakes, streams. Most will infiltrate (soak into) the ground and will collect as underground water.
The water cycle is powered by the sun's energy and by gravity. The sun kickstarts the whole cycle by heating all the Earth's water and making it evaporate. Gravity makes the moisture fall back to Earth.
