Answer:
Explanation:
All the energy in oil, gas, and coal originally came from the sun, captured through photosynthesis.for example when we burn wood to release energy that trees capture from the sun, we burn fossil fuels to release the energy that ancient plants captured from the sun. We can think of this energy as having been deposited in a natural solar power bank over millions of years.
So, in one sense, gasoline-burning cars, coal-burning power plants, and homes heated by natural gas are all solar powered!
Answer:
1.26m/s; 4.96m/s
Explanation
Acceleration is defined as the change I'm velocity of an object with respect to time.
Mathematically,
Acceleration (a) = change in velocity (v-u)/time (t)
Where v is the final velocity
u is the initial velocity
From the equation, it can be deduced that;
v = u+at
If the runner had an initial vertical velocity of -0.7 m/s over a period of 0.2seconds, its final velocity;
v = (-0.7)+9.81(0.2) (a=g=9.81m/s²)
v = -0.7+1.962
v = 1.26m/s
If the runner had an initial horizontal velocity of 3 m/s over a period of 0.2seconds, its final velocity;
v = 3+9.81(0.2)
v = 3+1.962
v = 4.96m/s
You can tell if vector is an unit because it has something to do with taking the magnitude of the vector.
also has a length 1. thus you should use pythagoras to check.
Hope this help
The second runner must run 3.3m/s. If the leading runner is 1.5 seconds ahead and there are 30m left, the second runner would need to run slightly faster than the lead in order to finish at the same time. To calculate this I did 30/1.5 which gave me 0.05. I added this onto the speed of the lead runner to get 3.3m/s :)
The lower the value of the coefficient of friction, the lower the resistance to sliding.
<u>Explanation:</u>
The coefficient of friction defines as directly proportionate with the resisting force, which is the frictional force. Hence, if there seems a decrease at coefficient of friction, then it is sure that the frictional force decreases.
We know that the frictional force on a body, is the product of coefficient of frictions and the normal forces acting on the body. Note that friction acts only, if a body is in contact, and it is of three types, static, kinetic and rolling.