Answer:
Mass – The single most important property that determines other properties of the star. Luminosity – The total amount of energy (light) that a star emits into space. Temperature – surface temperature, closely related to the luminosity and color of the star
Explanation:
Answer:
a. negative
b. zero
Explanation:
work is the change in the energy of a system due to external forces
work is done when a force moves a load through a distance in the direction of the force
The work done by a force on a system is positive when the force and the force displacement point in the same direction and negative when they point in opposite directions
in the scenario we are considering in the question, the force (the hand) moves the block vertically upwards but the displacement of the block reduces (in the opposite direction) since it decelerates. as such the work done by gravity on the block is negative.
the work done on the block is zero if the system consists of the block and the earth because there is no gravitational force exerted on the system
Answer:
63.8 V
Explanation:
We are given that
Potential difference,V=140 V
We know that
According to question
In series
Potential across 1.2 square cm=
Hence, the voltage across the 1.2 square cm wire=63.8 V
(150 km/hr) x (1000 m/km) x (hr/3600sec) = 41-2/3 m/sec
Acceleration = (change in speed) / (time for the change)
Change in speed = (41-2/3 minus 0) = 41-2/3 m/s
Time for the change = 0.5sec.
Acceleration = (41-2/3 m/s) / (0.5 sec) = 83-1/3 m/s² .
Acceleration of gravity = 9.8 m/s² .
Acceleration of sneezed air = (83-1/3) / (9.8) = <em>8.5 g </em>(rounded)