Answer:
C and E
Explanation:
I think that is the answers
Q:A hiker determines the length of a lake by listening for the echo of her shout reflected by a cliff at the far end of the lake. She hears the echo 2.0 after shouting. Estimate the length of the lake in meters. The speed of sound in air is 343 m/s.
Answer:
343 m.
Explanation:
Echo: This is the sound heard after the reflection of sound wave in a plane surface.
v = 2x/t.......................... Equation 1
Where v = speed of sound in air, x = length of the lake, t = time the echo was heard.
making x the subject of the equation,
x = vt/2....................... Equation 2
Given: v = 343 m/s, t = 2 s
Substitute into equation 2,
x = 343(2)/2
x = 343 m.
Hence the length of the lake in meters = 343 m.
21.2*4.184 = 88.7008
(also can i have brainliest pls? thx!)
Answer:
D.
Explanation:
The statement is not correctly written, the correct form is now described:
A particle with charge is moving in the positive z-direction at 5 meters per second. The magnetic field at its position is . What is the magnetic force on the particle?
From classic theory on Magnetism, we remember that the magnetic force exerted on a particle (), measured in newtons, is determined by the following vectorial formula:
(1)
Where:
- Electric charge, measured in coulombs.
- Velocity of the particle, measured in meters per second.
- Magnetic field, measured in teslas.
If we know that , and , then the magnetic force on the particle is:
Which corresponds to option D.
The mathematical definition of work (W) is force (F) multiplied by distance (x). In order to determine the distance for fixed force and work the above equation needs to be rearranged to make x the subject. The work divided by the force is equal to the distance. In this case the mother can push the baby carriage by a distance equal to 2920 divided by 62, which is 47.1 metres.