Answer:
A )
Explanation:
This change in frequency observation occur due to doppler effect
if the wave source moves,In the time between one wave peak being emitted and the next, the source will have moved so that the shells will no longer be concentric. The wavefronts will get closer together in front of the source as it travels and will be further apart behind it. (see the graph)
when the person standing still in front of the ambulance, he will observe a <em>higher frequency </em>than before as the source travels towards them.
The pitch we hear depends on the frequency of the sound wave.
A high frequency corresponds to a high pitch
as we hear a higher frequency , it makes the <em>pitch higher</em> too
Answer:
Time taken to stop = 6 sec
Explanation:
Given:
Rotation of wheel = 1.10 × 10² rev/min
Final velocity (v) = 0
Angular acceleration (a) = - 1.92 rad/s²
Find:
Time taken to stop
Computation:
Initial velocity (u) = (1.10 × 10² × 2π rad) / 60 sec
Initial velocity (u) = 11.52 rad / sec
We know that,
V = U +at
t = (v-u)a
t = (0 - 11.52) / (-1.92)
Time taken to stop = 6 sec
The answer is (B. The study of Matter and Energy) but technically you could consider physics all of these as engineering is based on physics and that would be the study of inventions, chemistry and biology were both discovered because of physics, and physics invokes more math than any other subject as it applies math to the entire Universe.
Answer:
266 g or 0.266 kg
Explanation:
The formula for specific heat capacity is given as,
Q = cm(t₂-t₁) ..................... Equation 1
Where Q = Heat Energy, c = specific heat capacity of Aluminum, m = mass of the aluminum fins, t₁ = initial temperature, t₂ = final temperature.
make m the subject of the equation,
m = Q/c(t₂-t₁)................... Equation 2
Given : Q = 2571 J, c = 0.897 J/g.°C, t₁ = 15.73 °C, t₂ = 26.50 °C.
Substitute into equation 2
m = 2571/[0.897×(26.5-15.73)]
m = 2571/9.661
m = 266 g or 0.266 kg
Hence the mass of the Aluminum fins = 266 g or 0.266 kg
Answer: a. Place the object on one side of a lever at a known distance away from the fulcrum. Place known masses on the other side of the fulcrum so that they are also paced on the lever at known distance from the fulcrum. Move the known masses to a known distance such that the lever is in static equilibrium.
d. Place the object on the end of a vertically hanging spring with a known spring constant. Allow the spring to stretch to a new equilibrium position and measure the distance the spring is stretched from its original equilibrium position.
Explanation:
The options are:
a. Place the object on one side of a lever at a known distance away from the fulcrum. Place known masses on the other side of the fulcrum so that they are also paced on the lever at known distance from the fulcrum. Move the known masses to a known distance such that the lever is in static equilibrium.
b. Place the object on a surface of negligible friction and pull the object horizontally across the surface with a spring scale at a non constant speed such that a motion detector can measure how the objects speed as a function of time changes.
c. Place the object on a surface that provides friction between the object and the surface. Use a surface such that the coefficient of friction between the object and the surface is known. Pull the object horizontally across the surface with a spring scale at a nonconstant speed such that a motion detector can measure how the objects speed as a function of time changes.
d. Place the object on the end of a vertically hanging spring with a known spring constant. Allow the spring to stretch to a new equilibrium position and measure the distance the spring is stretched from its original equilibrium position.
Gravitational mass simply has to do with how the body responds to the force of gravity. From the options given, the correct options are A and D.
For option A, by balancing the torque, the mass can be calculated. Since the known mass and the distance has been given here, the unknown mass can be calculated.
For option D, here the gravitational force can be balanced by the spring force and hence the mass can be calculated.
