What does the gradient on a distance time graph represent?
What does gradient of the line on a velocity time graph represent?
The stopping distance of a vehicle is the equal to:
the sum of the reaction time and the braking time
the sum of the breaking distance and the distance travelled in during the reaction time
the sum of the thinking distance the breaking time
the sum of the thinking distance and the breaking distance
the product of the breaking time and the thinking distance
the current potential difference graph for a resistor at a constant temperature is:
y=x until halfway up the graph where it remains as y= (halfway up the y scale)
The greater the resistance, the __________ the current, for a component at a given _________.
For components connected in series:
the total resistance is the sum of the resistance in all the components
the P.D is the same across all the components
the charge is constantly changing in all the components
same current through each component
the total current through the whole circuit is the sum of the currents through the separate components.
the potential difference of the supply is the shared between the components
Mains electricity is a.c.
Mains electricity has a frequency of:
The units of charge are
What comes directly after the main sequence of a star about the size of our sun?
red super giant
One eventual outcome for a huge star is a black hole, what is the other?
The current through a resistor is inversely proportional to the potential difference across the resistor.
RCCBs operate by detecting a difference between:
The temperature of the wire and its surroundings
The resistance in the plug and in the appliance.
The current in the live wire and the current in the neutral wire.
The voltage in the live wire and the current in the neutral wire.
The voltage in the live wire and the voltage in the neutral wire.
The frequency of Ultrasound is:
20Hz to 20kHz
20kHz to 200kHz
20Hz to 200Hz
The equivalent of the retina in a camera is the film.
In an optical fibre cable, the light is totally internally reflected because the angle of incidence always remains:
greater than the angle of refraction.
equal to the angle of refraction
smaller than the angle of refraction.
greater than the critical angle.
equal to the critical angle.
smaller than the critical angle.
If an object is turning, the clockwise moment must be exactly balanced to the anticlockwise moment.
In the motor effect, the size of the force can be increased by:
Increasing the voltage
Increasing the current
Increasing the charge
Increasing the size of the magnet
increasing the magnetic field strength
In a step up transformer the p.d across the secondary coil is greater than the p.d across the primary coil.
Switch mode transformers work at a _________ frequency