physics 3-7
the ke of a 900kg car whose speed is 60km/h
125kj
the musical note of 440Hz and its wavelength in seawater is 3.5m the speed of sound of the seawater is
1540 m/s
when a ton of coal burns, it loses 3.3 x 10^7 kg of mass the energy given off is
3.0 x 10^-10
the height above the ground of a child on a swimng varies from 0.5m at the lowest point to 2.0m at the highest point the maximum speed of the child is
5.4m/s
the density of air is 1.3kg/m^3. the air in a room 5m long, 4m wide, and 2.5m high has what mass?
65kg
three 12-v batteries cannot be connected to give a voltage for the set of
6V
ethanol boils at 172°F the celsius equivalent is?
78°C
an 800kg car moving at 80km/h collides head on with a 1200 kg car moving at 40km/h in the opposite direction if they stick together the wreckage now has an initial speed of
8km/h
the frequency that isnt an overtone if the fundamental frequency F is
F/2
when someone moves past a stationary electric charge they detect?
both electric and magnetic fields
the max possible efficiency of a heat engine?
depends on the ratio between the exhaust and intake temp
which if the following isnt a property of an electromagnetic wave
electric charge
a proton in an atom circulates around its nucleus
false
rolling a ball up an inclined plank requires an amount of work proportional to the
height the ball is raised
the current of 20 ohm electric heater operated at 240v
is 12A
temperature increase doesnt depend on?
its shape
which of the following is not a unit of power
joule-second
first law of thermodynamics
law of conservation of energy
which one or more of the following is a vector quantity
linear momentum and angular momentum
a molecule that has lost an electron becomes
positive ion
P1/T1=P2/T2
relationship between pressure & absolute temp
a pure musical note causes a wooden panel to vibrate this is?
resonance
what waves cant be polarized?
sound waves
a golf ball and a ping pong ball are dropped in a vaccum chamber when they have fallen halfway down they have the same?
speed
something with the greatest mass also has?
the greatest density
2 charges if +Q are 1cm apart, if one charge is replaced by a charge of -Q, the magnitude of the force between them is
the same
which of the following quantities is always the same all observers
the speed of light
does water have the highest specific heat?
true
red has the longest wavelength
true
example of a wave that is partially longitudinal and partly transverse?
water waves
gravitational force between two protons is?
weaker
