Answer:
B) 40 km West
Explanation:
Let position of B is origin so with respect of City B the position of A is given as
south of city B
now Bus starts from City A and travels a distance of 50 km at 37 degree North of East to reach city C
so it is


now the position of C is given with respect to A
in order to find the position of C with respect to B we can say



so in order to reach at city B from city C bus has to travel 40 km towards West
Answer: 55 ohms
Explanation:
Given that,
Voltage of heater (v) = 110-volt
Current drawn by heater (I) = 2.0 amperes
resistance of the heater (r) = ?
Since voltage, current and resistance are involved, apply the formula for ohms law.
Voltage = current x resistance
i.e v = ir
where r = v / i
r = 110 volts / 2.0 A
r = 55 ohms
Thus, the resistance of the heater is 55 ohms
Answer:
Where the electric potential is constant, the strength of the electric field is zero.
Explanation:
As a test charge moves in a given direction, the rate of change of the electric potential of the charge gives the potential gradient whose negative value is the same as the value of the electric field. In other words, the negative of the slope or gradient of electric potential (V) in a direction, say x, gives the electric field (Eₓ) in that direction. i.e
Eₓ = - dV / dx ----------(i)
From equation (i) above, if electric potential (V) is constant, then the differential (which is the electric field) gives zero.
<em>Therefore, a constant electric potential means that electric field is zero.</em>
Thermostat is used to control the temperature in a room
Mechanical advantage<span> <span>is a measure of the force amplification
achieved by using a tool, </span>mechanicaldevice or
machine system. Ideally, the
device preserves the input power and simply trades off forces against movement
to obtain a desired amplification in the output force. The model for this is
the law of the lever. So the ima is 3/1.5 = 2</span>