2. Physics - Q&A
134 questions found
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For a heat pump to internally heat it uses a
- inside evaporator.
- inside condenser.
- inner evaporator.
please help
A good refrigerant has a
- low condensation temperature and high condensation pressure.
- low condensation temperature and low condensation pressure.
- high condensation temperature and low condensation pressure.
kindly explain
In a heat pump
- the evaporator gains heat in cycles.
- the condenser always loses heat flow.
- the pump operates in both directions.
kindly explain
You are at the north pole where the temperature is minus 50 degrees C below freezing. What sort of thermometer would you use to measure it?
- Water.
- Alcohol.
- Mercury.
i don't get it guys
A body rotating at an angular velocity of 5 radians/sec, with a radius of 5 metres has a speed of
- 5pi metres per second.
- 5 metres per second.
- 25 metres per second.
please i need eplanation with formular
A force perpendicular to a beam produces what type of stress?
- axial.
- shear.
- radial
i think the answer is tensile stress,becouse its given by force perpendicular to the cross sectional area/cross section area....kindly someone explain to me why SHEAR
1 degree rise on the centigrade scale will cause a
- 1.8 degree rise in Fahrenheit.
- 33 degree rise in Fahrenheit.
- 2.5 degree rise in Fahrenheit.
kindly someone explain for me
Oxygen, atomic number 8 is
- divalent.
- covalent.
- bivalent.
can someone explain
A vessel has 25 ml of water which produces 10 kPa. If another 125 ml of water is added, what will be the pressure in the vessel?
- 40kPa
- 50kPa
- 60kPa
someone explain please
A mass of 400kg moves 27 metres with a force of 54N. What is the work produced?
- 2916J.
- 729 J.
- 1458J.
pls explain
A body drops from 10m, it will hit the ground in
- square_root(5 seconds).
- square_root(4 seconds).
- square_root(2 seconds).
What formula is used for this?
In a concave mirror, a light ray passing through the focal point will be reflected
- through the midpoint.
- toward the focal point
- parallel to the axis.
it is parallel to axis or it is on the axis.? why not through the focal point or on the center line of the mirror?
If, with a concave mirror the image is placed beyond the centre of curvature, the image produced will be
- virtual, erect and larger.
- real, inverted and smaller.
- real, inverted and enlarged.
WRONG QUESTION OBJECT NOT IMAGE
Ignoring friction, if you let an object slide down a slope, at the bottom
- the potential energy is equal to the kinetic energy.
- the potential energy is more than the kinetic energy.
- the kinetic energy is more than the potential energy.
CAN YOU PLEASE EXPLAIN HOW?
Brownian Movement describes
- the bonding of molecules.
- the fission of molecules.
- the motion of molecules.
Analyse brownian movement
When an open pipe is played and a note is heard
- the lowest frequency of the note is called second harmonic.
- resonance occurs with standing waves set up inside the pipe.
- the fundamental frequency is always twice the pipe diameter.
please explain.
A good refrigerant has
- high condensing pressure, low evaporating temperature.
- high condensing pressure, high vaporating temperature.
- low condensing pressure, low vaporating temperature.
will you please explain the reason??
A ram has a piston with 2 in2. Another ram with a piston of 4 in2 will provide
- triple the force.
- double the force.
- square the force.
Hi, I could do with some help on this question. I have not see this method of specifying a ram and piston combination. What is the difference between a "2 in2" and a "4 in2" piston, are the designations relating to piston and rod diameter? Thanks, Graeme.
A cylinder filled with water to half a metre will exert a pressure of
- 49.0 Pa.
- 4900 Pa.
- 9800 Pa.
Hi, can someone please explain?
A spring, operating within its elastic range, shortens by 60mm when a load of 480N is applied to it. Calculate the total shortening when the load is increased by 120N
- 82mm.
- 45mm.
- 75mm.
Hi, can someone give me the formula to calculate this?
When light rays enter a medium with a different refractive index they
- split in two.
- stay aligned.
- change speed.
Will it not change direction too?
The landing speed of an aircraft is 54 m/s. If the maximum deceleration is 3m/s2 the minimum length of runway required is
- 162m.
- 486m.
- 360m.
solve pls
A mass on a spring nearly hits the ground 20 times a minute, its frequency is
- 3 cycles per second.
- 1/3 cycle per second.
- 20 cycles per second.
Kindly explain with formula
The oscillation produced by a pendulum 2500mm long has a periodic time of
- 6 seconds.
- 3 seconds.
- 9 seconds.
Kindly explain with formula
A lifting machine moves with an effort, a distance of 200 cm, in order to raise it 0.5 m. The Velocity Ratio is
- 8.
- 4.
- 2.
Kindly explain with formula