Answer:
it is reduced four times.
Explanation:
By definition, the electric field is the force per unit charge created by a charge distribution.
If the charge creating the field is a point charge, the force exerted by it on a test charge, must obey Coulomb´s Law, so, it must be inversely proportional to the square of the distance between the charges.
So, if the distance increases twice, as the force is inversely proportional to the square of the distance, and the square of 2 is 4, this means that the magnitude of the force exerted on the test charge must be 4 times smaller.
Answer:
A. Mass
Explanation:
Inertia of an object is the resistance of the object to any change in its state of motion: it means that if an object is at rest, it tends to stay at rest for inertia (unless a net force acts on it), and if it is moving, it tends to continue moving with the same velocity, for inertia.
The inertia also describes how difficult it is to stop/accelerate an object, and it is directly proportional to the mass of the object: in fact, the larger the mass of an object, the more difficult it is to change its state of motion, and this means it has greater inertia.
Answer:
14.3kg
Explanation:
Given parameters:
Quantity of heat = 149000J
Change in temperature = 5.23°C
specific heat of the ice = 2000J/kg°C
Unknown:
Mass of the ice in the bag = ?
Solution:
The heat capacity of a substance is given as:
H = m c Ф
H is the heat capacity
m is the mass
c is the specific heat
Ф is the temperature change;
since m is the unknown, we make it the subject of the expression;
m = H/ mФ
m = 
= 14.3kg
Answer:
A kilowatt (kW) is a unit of power.
Explanation:
The power of an object is given by :
Here,
E is the energy required
t is time
The SI unit of power is Watts and the SI unit of energy is Joule. the commercial unit of energy is kilowatt per hour.
Option (1) : A kilojoule (kJ) is a unit of power is incorrect.
Option (2) : A gigawatt (GW) is a unit of energy is incorrect.
Option (3) : A watt (W) is a unit of energy is incorrect.
Option (4) : A kilowatt x hour per year (kWh/yr) is a unit of energy is incorrect.
Option (4) : A kilowatt (kW) is a unit of power is correct.
Hence, the correct option is (d).
Answer:
simple, Volt =change in potential energy/Charge
the unit of energy is newton meter (Force*distance)
the unit of charge is coloumb
So, Volt/meter=newton* meter/coloumb*meter
=newton/coloumb (hence proved)
This unit is the potential drop per unit of length in a conductive wire with uniform resistance
