Answer:
18min
Explanation:
v=d/t
t=d/v= 27/90 =0.3hrs =18min
Answer:potential difference is more or less like voltage. Using ohms, V=IR
Where V is Voltage
I is Current =0.4A
R is Resistance=20ohms
V=0.4*20
V=8V
Hence the potential difference will be 8V.
ii) V=0.4*30
V=12V
Explanation:
The voltage of potential difference is directly proportional to the current and the resistance. So if one increase or decrease, it will have impact on the other.
From the calculations, when the resistance increase, the voltage will increase to appreciate the change.
The answer of a & b are force of cohesion and force of adhesion
Of rest two answers I don't know
Answer:
Explanation:
a ) Temperature at ground level is a field and it is scalar field .At any point in space near ground level , the temperature is specific so it is a field . It is scalar because temperature has no direction .
b )
Wind velocity at 100 feet above the ground is also a field but it is a vector field . At any point in space , the wind velocity is specific so it is a field . It is vector because velocity has a particular direction at any point .
c )
Gravitational force on Roessler Hall is a vector field because gravitational force also depends on location in space and it has direction.
d )
Height of a person in your group is not a space because it does not depend upon location is space . It is same for all location .
e )
Height (above sea level) of the ground is a field because it also depends upon location in space . It is scalar field .
f )
Slope of the surface of the earth is a scalar field .
Answer:
Just above the pole (top-most red circle)
Explanation:
Polaris is used to identify North direction. Since, the Earth rotates on its axis which is along North-south, Polaris never seems to rise and set from the Northern hemisphere. This is because Polaris lies above north pole. Thus, in the given diagram, Polaris is above the North pole on the axis represented by top-most red circle.
