Answer:
A. Heat flows from an object at higher temperature to an object at lower temperature
Explanation:
The option A obeys the 2nd law of thermodynamics. The heat will flow from the object at higher temperature to the object at Lower temperature till they reach an equilibrial state.
Heat doesn’t necessarily flow from an object with higher thermal energy to an object with lower thermal energy because an object has a higher thermal energy when it’s mass is more than the other. This makes B wrong.
C is wrong because heat moves from an object with higher temperature to objects with Lower temperature regardless of the state of matter.
Explanation:
Downstream: you just sum the magnitude of the velocity vectors:
3km/h + 4km/h = 7km/h
Upstream: difference of the magnitudes of the velocity vectors, in absolute value:
|3km/h - 4km/h| = 1km/h
Force = (mass) x (acceleration) Newton's second law of motion.
Force = (2 kg) x (3 m/s²) = 6 newtons.
An object moving in a circle is accelerating. Accelerating objects are objects which are changing their velocity - either the speed or the direction. An object undergoing uniform circular motion is moving with a constant speed.
Answer:
Acceleration = 311.2 Km/hr²
Explanation:
Given: Radius of the Orbit r= 3.56 × 10⁶ km
Period of the orbit = 28 days = 672 hrs
Sol: We have Fc = MV²/r
⇒M ac = MV²/r
⇒ac = V²/r
First we have to Speed V so for this we have to find the circumference ( distance covered by the moon in one orbit)
⇒ Circumference= 2 π r
= 2 × 3.13149 × 3.56 × 10⁶ km
= 22,368,139.69 Km
Now Speed = Distance /time
Speed = 22,368,139.69 Km / 672 hrs
Speed V = 33,285.92 Km/Hr
Now
ac = V²/r = (33,285.92 Km/hrs)² / 3.56 × 10⁶ km
ac = 311.2 Km/hr²