Frequency (f) = 500 hz (SI)
Velocity (V) = 1250 m/s (SI)
Wavelength (Lambda) = ? meters

For speed you can differentiate the equation, for acceleration you can again differentiate the equation .
at t=0 the particle is slowing down , when you get equation for velocity put t=0 then only -1 is left
Answer:
m=ρV
V=4/3 * pi * r3
V=1.3 * 3.14 * 3.9^3
V=242.14 cm^3
m=7.58 * 242.14
m=1.8 kG
Explanation:
1. We calculate volume for sphere.
2. Then we calculate mass of sphere.
Answer:
B. Fluorescent lamps operate at a higher temperature than incandescent
Explanation:
Fluorescent lamps have a number of advantages over incandescent lamps which are given in the options given in A, C and D. The option available in B is a drawback, not an advantage. This is because it can give out and radiate more heat as a result of working at a higher temperature. Hence B option is correct.
The true statements about magnetic fields and forces will be A,D and E.
<h3>What is a magnet?</h3>
An iron piece,alloy, or other substance with its constituent atoms arranged in such a way that it shows magnetism qualities,
The function of the magnet is attracting other iron-containing objects or aligning itself in a magnetic field.
There are two poles of the magnet;
1. North Pole.
2. South Pole.
The same poles repel each other, while the opposite poles attract each other. In a sense, south-south and north-north repel. While the north-south and the south-north attract each other.
The correct statements are;
(A). The north pole attracts the south pole of a magnet.
(D)Forces caused by magnetic fields are weaker farther from the magnet.
(E)Magnetic forces can act on an object even if the object isn't touching the magnet.
Hence, the true statements about magnetic fields and forces will be A,D and E.
To learn more about the magnet, refer to the link;
brainly.com/question/13026686
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