Test 9 completed Flashcards
Unit for spring constant?
N/cm
How to make the resultant force greater for an object traveling in circles? {3 points}
- Bigger mass
- Bigger speed
- Smaller radius
A ball hits an object. Calculate the velocity of the object.
momentum=momentum
ball p = ball p + object p
ball bounces backwards, so velocity is negative
The wavelength is smaller than the gap.
less curved
The current–voltage graph of a filament lamp , explain its shape.
As the temperature increases, resistance increases, so more voltage is required for the same increase in current.
State what is at point X to produce the field pattern shown in Fig. 7.1.
positive point charge
With friction, electrons are..
lost
Explain how the structure of an electrical conductor differs from the structure of an electrical
insulator.
Conductors have free electrons
How does one wavelength look like?
Two halves on the top
A graph to represent a.c as a coil turns. What does one turn look like? What do the peaks and troughs look like? The position at 0?
One turn is one wavelength.
The peaks are horizontal.
At 0, they are vertical.
Household smoke alarm:
type of radioactive emission-
explanation-
half-life-
alpha, highly ionising, 100 years
measuring the thickness of aluminium strips produced in a factory
type of radioactive emission-
explanation-
half-life-
beta
absorption depends on thickness of aluminium
any number of years
State two different sources of background radiation.
- radon gas (in the air)
- rocks OR buildings
- food OR drink
- cosmic rays
Hubble’s law equation and what is it
Hubble’s constant: H0=d/v
Hubble’s law:
v=H0d
Distant galaxies are moving away from Earth with a speed, v, proportional to their distance, d from Earth
Numerical value of Hubble’s constant?
2.2 x 10^-18
