I) You walk barefoot on the hot street and it burns your toes.
The road is in direct contact with your skin. Thermal energy from the road will transfer to the bottom of your feet, then to the rest of your body. This is an example of conduction.
II) When you get into a car with hot black leather in the middle of the summer and your skin starts to get burned.
Just like in the previous example, the hot leather is in direct contact with your skin (I guess if you're going to drive naked). Thermal energy from the leather will transfe to your skin, then to the rest of your body. This is also conduction.
III) A flame heats the air inside a hot air balloon and the balloon rises.
The flame heats air directly at the bottom of the balloon. The warm air expands and becomes less dense. This will rise and let the unheated, denser air in the balloon fall down toward the flame. This is an example of the convection cycle.
IV) A boy sits to the side of a campfire. He is 10 feet away, but still feels warm.
The campfire heats air directly nearby. The warm air expands and moves away from the fire in all directions, leaving behind unheated, denser air to be heated up. Some of the warm air reaches the boy. This is another example of convection.
The answer is A) 1 and 2.
Answer:
Terminal velocity of object = 12.58 m/s
Explanation:
We know that the terminal velocity is attained when drag force and gravitational force are of the same magnitude.
Gravitational force = mg = 80 * 9.8 = 784 N
Drag force = 
Equating both, we have
So v = 12.58 m/s or v = -15.58 m/s ( not possible)
So terminal velocity of object = 12.58 m/s
Answer:
a) a = 3.09 m/s²
b) aₓ = 2.60 m/s²
Explanation:
a) The magnitude of her acceleration can be calculated using the following equation:
<u>Where</u>:
: is the final speed = 8.89 m/s
: is the initial speed = 0 (since she starts from rest)
a: is the acceleration
d: is the distance = 12.8 m
Therefore, the magnitude of her acceleration is 3.09 m/s².
b) The component of her acceleration that is parallel to the ground is given by:
<u>Where</u>:
θ: is the angle respect to the ground = 32.6 °
Hence, the component of her acceleration that is parallel to the ground is 2.60 m/s².
I hope it helps you!
Answer:Both are correct
Explanation:
Both are correct because
Mechanical efficiency is the dimensionless term which is the ratio of brake horsepower to the Indicated horse Power
Where brake power is the Power obtained at the crankshaft and
Indicated horsepower is the power obtained in the combustion chamber and this power is the loss in the form of friction.
Volumetric efficiency is the ratio of actual fuel intake to the maximum air fuel that could be taken.
This is a sneaky trick question, to help you discover whether you know
one of the differences between velocity and speed.
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If you make a list of the distances and directions, and ignore the times,
you find these:
4 - west, (3 + 1) - east . . . . . zero in the east/west direction
1.5 - north, 1.5 - south . . . . . zero in the north/south direction
This jogger went out, had a nice jog around the neighborhood,and ended up exactly where he started.
Average velocity = (distance between start point and end point) / (time)
IF the question asked for average SPEED, then you would need the total distance, and divide it by the total time. But it asks for VELOCITY, and <u>that</u> only involves the straight distance between the start point and the end point, regardless of the route taken in between.
The jogger ended up exactly where he started. The distance between start and end points was zero. Average velocity is (zero) / (time) . And that fraction is going to be <em><u>Zero</u></em>, no matter how long or how short the trip was, and no matter how much time it took.
