If your speed changes from 10 km/h to 6 km/h then
you have an acceleration.
Whether it's a positive or negative one completely depends
on which direction you decided to call the positive direction,
when you started considering your speed and its changes.
If you decided to call the direction in which you're traveling
the positive direction, then a decrease in your speed is a
negative acceleration.
But you could just as easily have said that you're traveling
in the negative direction. If you did that, then a decrease in
your speed would be a positive acceleration.
It's completely up to you, and how you define things.
Answer:
a) 6.4 kJ
b) 43.4 kJ
Explanation:
a)
= Heat absorbed = 37 kJ
= Coefficient of performance = 5.8
= Work done
Heat absorbed is given as
=
37 = (5.8)
= 6.4 kJ
b)
= work per cycle required
= +
= 37 + 6.4
= 43.4 kJ
Answer:
because of the raindrop velocity relative of the car has a vertical and horizontal component
Explanation:
- The car moves in a <em>horizontal direction </em>relative to the ground. The raindrops fall in the <em>vertical direction</em> relative to the ground.
- Their velocity relative to the moving car has both vertical and horizontal components and this is the reason for the diagonal streaks on the side window.
-
The diagonal streaks on the windshield arise from a different reason.
-
The drops are pushed off to one side of the windshield because of air resistance.
Answer:
B
Explanation:
Protons have a positive electrical charge of +1,
Electrons have a negative charge of -1,
Neutrons have a neutral charge of about 0.
Explanation:
thomas edison and Nikola tesla were involved in the war of currents
