Answer:
204 m
Explanation:
When the marble is dropped from a certain height, its gravitational potential energy converts into kinetic energy. So the kinetic energy gained is equal to the variation of gravitational potential energy:
where
m is the mass of the marble
g = 9.8 m/s^2 is the acceleration of gravity
is the change in height
In this problem, we have
m = 50 g = 0.05 kg
Solving the formula for , we find the necessary height from which the marble should be dropped:
Answer:
See explanations below
Explanation:
For resistors in series, the will be added for those in parallel, we will take the sum of their reciprocal
A) 3 2ohms resistors in series
Equivalent resistance = 2 + 2 + 2
Equivalent resistance = 6ohms
B) 2 4 ohms resisstors in parallal
1/R = 1/4 + 1/4
1/R = 2/4
R = 4/2
R = 4ohms
Equivalent resistance is 2ohms
C) 4 ohms with in series with 8ohms = 4 + 8
Equivalent resistance = 4 + 8
Equivalent resistance = 12ohms
D) 4 ohms and 2 ohms in parallel is expressed as;
1/R = 1/4 + 1/2
1/R = 1+2/4
1/R = 3/4
R = 4/3
4/3 ohms in series with 6ohms
Equivalent resistance = 4/3 + 6
Equivalent resistance =4+18/3
Equivalent resistance = 22/3 ohms
<span>362 seconds, or 6 minutes, 2 seconds.
This is an exercise in the conservation of momentum.
For this problem, I'll use the initial coordinates and velocity of the astronaut as my frame of reference because it makes the math easier. Due to the law of conservation of momentum, the momentum before and after the astronaut throws the wrench has to remain the same. And since I'm using the starting situation of the astronaut as my frame of reference, that value is 0. But thankfully, momentum is a vector quantity and we can save the astronaut.
The momentum of an object is mass times velocity. So the momentum of the wrench after being thrown is:
-19.6 m/s * 0.515 kg = -10.094 kg*m/s
Now to balance that, we need the astronaut to have a momentum of 10.094 kg*m/s which just happens to be the case (can't break the laws of physics). So let's do some division to get the velocity.
10.094 kg*m/s / 86.8 kg = 0.116290323 m/s
Yay! The astronaut is moving back to the shuttle at a reasonable velocity. But has 42.1 m to travel. Another situation for division:
42.1 m / 0.116290323 m/s = 362.0249653 s
So rounding to 3 significant digits gives a travel time of 362 seconds, or just a couple of seconds longer than 6 minutes.</span>
Answer: its the second (B) option, n1sintheta1=n2aintheta2
theta is the thing that looks like a 0 with the across.
Explanation: I got it right
