Answer:
a) -3.267 m/s
b) 2.227 m/s
Explanation:
As per the conservation of momentum
m1v1 + m2v2=0
m1= mass of log
m2 = mass of lumber jack
v1 = velocity of log
v2 = velocity of lumber jack
a) Velocity of first log
m/s
b) m1v1 + m2v2 = m3v3
Velocity of log
= 
A transformer increases and decreases voltage.
Answer:

Explanation:
From the given information, the LED is operating with a given wavelength of 850 nm or 0.85 μm.
Hence, the material dispersion is 
Now, using the pulse spread formula:


Thus, the pulse spreading as a result of material dispersion is:
Daniddmelo says it right there, don't know why he got reported.
The potential energy (PE) is mass x height x gravity. So it would be 25 kg x 4 m x 9.8 = 980 joules. The child starts out with 980 joules of potential energy. The kinetic energy (KE) is (1/2) x mass x velocity squared. KE = (1/2) x 25 kg x 5 m/s2 = 312.5 joules. So he ends with 312.5 joules of kinetic energy. The Energy lost to friction = PE - KE. 980- 312.5 = 667.5 joules of energy lost to friction.
Please don't just copy and paste, and thank you Dan cause you practically did it I just... elaborated more? I dunno.
Answer:
Check the first and the third choices:
<u><em /></u>
- <u><em>a. The temperature of a gas is directly proportional to its volume</em></u>
- <u><em>b. The temperature-to-volume ratio of a gas is constant.</em></u>
Explanation:
Rewrite the table for better understanding:
Temperature of gas (K) Volume of gas (L)
298 4.55
315 4.81
325 4.96
335 ?
Calculate the ratios temperature to volume with 3 significant figures:
Then, those numbers show a <u><em>constant temperature-to-volume ratio</em></u>, which may be expressed in a formula as:
- Temperature / Volume = constant, which is a directly proportional variation (the volume increases in a constant proportion to the increase of the temperature).
Hence, the correct choices are:
- The temperature of a gas is directly proportional to its volume (first statement), and
- The emperature-to-volume ratio of a gas is constant (third statement).