Answer:
3.3 seconds I believe
Explanation:
A water skier is towing by motorboat at a constant velocity of magnitude 15 km /h. The boat speed up, and after a short interval the skier is towed at a new constant velocity of magnitude 20 km/h. What is the net force on the skier when she is moving at 15 km/h? And at 20 km/h?
Answer:
The skier is experimenting a net force of 0 newtons in both cases. ([tex]v_{1} = 15\,\frac{km}{h}[/tex], [tex]v_{2} = 20\,\frac{km}{h}[/tex])
Explanation:
According to Newton's First Law, an object is in equilibrium when it is either at rest or moving at constant velocity, which means that net force is equal to 0 newtons.
Therefore, the skier is experimenting a net force of 0 newtons in both cases.
Which of the following solar oven design materials would serve as the best insulator to minimize the transfer of thermal energy from the inside of the solar oven to the surroundings?
1.white paper lining the interior
2.metal platform
3.foil on the exterior flap
4.layers of cotton lining the interior
Answer:
layers of cotton lining the interior
Explanation:
.
Answer in units of N.
How does a neutral atom change when its number of protons, electrons, or neutrons changes?
Answer:
A change in protons changes the element identity. A change in neutrons changes the element's atomic weight, but does not change the identity. More protons than electrons is a positive charge, more electrons than protons is a negative charge.
Explanation:
Question 7 (2 points)
To draw conclusions in the scientific method means to decide if the Hypothesis is supported or not supported.
O True
O False
Answer:
Tire
Explanation:
In order to see inside atoms, they are broken apart with high speed
neutrons or electrons ?
Answer:
i think its electrons
Explanation:
How would changing the mass of a bat affect a player’s ability to swing the bat and adjust the path of the bat to hit a moving baseball or softball?
Answer:
Explanation:
The answer to that question is "both," though past players tend to have used heavier bats than do today's players. Baseball's "king of swat" Babe Ruth reportedly began his hitting career using a 54 ounce (1.5 kg) hickory bat, and is known to have used a 40oz bat in 1927 when he hit his 60 home runs.[1] Ty Cobb and Joe Di Maggio both played with 42oz bats and Rogers Hornsby used a 50oz piece of lumber. George Sisler, playing for the St. Louis Browns in the 1920's, made his bat heavier by hammering Victrola needles into the barrel of his bat.[2] In the 1950's Cincinnati Reds' Ted Kluszeski hammered tenpenny nails into his bat to make it heavier.
Other great hitters including Ted Williams, Rod Carew and Stan Musial used much lighter bats: 31-33oz.[1] Roger Maris used a 33oz bat to hit his 61 home runs in 1961. Many players have tried to make their bats lighter by drilling a hole in the barrel and filling it with cork. Detroit Tigers' Norm Cash admitted to using a corked bat in 1961 when he won the batting title with a .361 average (though he slumped to .243 the next year with the same corked bat).[2]
Kirkpatrick[3] reports that Roger Maris participated in a 1962 experiment in which he batted for distance with 5 different new bats whose weights varied from 33 to 47oz. He hit 5 long fly balls with each bat and the distances were measured and correlated to bat weight. The heavier bats, on average, resulted in further distance. However, Maris' preferred bat (which he used to break Babe Ruth's home run record) was the lightest of the set, even though it produced the shortest distance fly balls. Mark McGwire used a 35oz bat to hit his 70 home runs in 1998, and Barry Bonds used a 32oz bat to hit his 73 home runs in 2001. Most of today's major league players typically use 31-35oz bats.
Physicists have shown,[3,4] from a simple collision analysis, that the optimum bat weight is between 15 and 18oz. However, no professional batter uses a bat this light (in fact, you cannot make a wood bat this light). NCAA regulations[x] recently imposed a -3 rule (length in inches minus weigh in ounces cannot exceed 3) so that 34 inch bats must weigh 31oz. So far no such rule exists for Little League play, and -12 composite bats were introduced for the 2003 season. This brings us back to our original questions: which is better: heavier or lighter bats? So, what is the optimum bat weight, and what criteria influence this choice? Let's start by looking at the collision between ball and bat.
ln the constellation of Orion, you can see a group of stars and other objects that appear in the shape of a sword. Ln the middle of the sword, a bright "fuzzy star" appears. Astronomers looking at this object through telescopes refer to it as a "stellar nursery."What is another name for this object?
Answer:
Nebula
Explanation:
Given that in the constellation of Orion, you can see a group of stars and other objects that appear in the shape of a sword. Ln the middle of the sword, a bright "fuzzy star" appears. Astronomers looking at this object through telescopes refer to it as a "stellar nursery." Another name for this object is called NEBULA.
The space where new stars are forming anew is known as nebulae
true for false; "Acceleration is inversely proportional to mass."
Answer:
True
Explanation:
F = ma
We can rearrange to a = F/m
So if we increase a and F is constant, then m has to decrease because it is in the denominator.
Which statement explains the similarity between momentum and kinetic energy of an object?
A. Both are inversely proportional to the mass and velocity of the object.
B. Both are directly proportional to the mass and velocity of the object.
C. Both are inversely proportional to force and displacement.
D. Momentum is directly proportional to the mass of the object and the square of the velocity of the object.
E. Kinetic energy is directly proportional to the mass of the object and the square of the velocity of the object.
Please help asap
Answer:
B. Both are directly proportional to the mass and velocity of the object.
Answer:
E. Kinetic energy is directly proportional to the mass of the object and the square of the velocity of the object.
Explanation:
I just took the test and it was right. Trust me on this one
Which of the following statements about the technique of hypnotic regression is not true?
O Recovered memories are not reliable.
Courts often depend upon recovered memories.
O Memories may be planted by the hypnotist.
The process may create stress for the subject.
Answer:
B. is the correct answer just took the topic review.
Explanation:
Edge2020. Hope that this helps! Peace and Love
Courts often depend upon recovered memories is the wrong statement about the hypnotic regression.
What is hypnotic regression?Hypnotic regression is a contentious method because it can have a number of negative effects on the subjects who undergo it. For the beginners, the memories recovered through any regression can be doubtful and not trust-worthy. All the suggestions or leading questions from the hypnotist or other people of witnesses can affect the memory.
The previous lives memories will be found by the hypnotic technique as a past life regression. If they used to remember the past life by this method they have high chance of getting into the traumas.
Regression therapy mostly used to identify the cause of your current thoughts and reactions. Therapists who is using this techniques to access subconscious memories that are guiding your current behaviour.
Regression therapy is a method of treatment that could approach and focuses on resolving particular past events that are thought to be interfering or relatable with a person's current mental and emotional well-being.
Hence, Option B is the correct answer.
Learn more about Hypnotic regression,
https://brainly.com/question/14703250
#SPJ6
Find the 7th term of the geometric sequence
1/8, 1/2, 2, ...
Answer:
512
Explanation:
Given sequence:
1/8, 1/2, 2, ...
Unknown:
The 7th term of the geometric sequence = ?
Solution:
To solve this problem, we apply the formula below;
Sₙ = arⁿ⁻¹
a is the first term
r is the common ratio
n is the nth term
r = [tex]\frac{\frac{1}{2} }{\frac{1}{8} }[/tex] = [tex]\frac{1}{2} x 8[/tex] = 4
Input the parameters and solve;
Sₙ = [tex]\frac{1}{8}[/tex] x 4⁷⁻¹
Sₙ = [tex]\frac{1}{8}[/tex] x 4⁶ = 512
“While the big bang theory is the most popular modern theory of how the universe formed, it is incomplete.” Which question does the big bang theory leave unanswered?
A freshly prepared sample of radioactive isotope has an activity of 10 mCi. After 4 hours, its activity is 8 mCi. Find: (a) the decay constant and half-life T1/2; (b) How many atoms of the isotope were contained in the freshly prepared sample? (c) What is the sample's activity 30 hours after it is prepared?
Answer:
(a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]
The half life is 11.3 hr.
(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]
(c). The sample's activity is 1.87 mCi.
Explanation:
Given that,
Activity [tex]R_{0}=10\ mCi[/tex]
Time [tex]t_{1}=4\ hours[/tex]
Activity R= 8 mCi
(a). We need to calculate the decay constant
Using formula of activity
[tex]R=R_{0}e^{-\lambda t}[/tex]
[tex]\lambda=\dfrac{1}{t}ln(\dfrac{R_{0}}{R})[/tex]
Put the value into the formula
[tex]\lambda=\dfrac{1}{4\times3600}ln(\dfrac{10}{8})[/tex]
[tex]\lambda=0.0000154\ s^{-1}[/tex]
[tex]\lambda=1.55\times10^{-5}\ s^{-1}[/tex]
We need to calculate the half life
Using formula of half life
[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{\lambda}[/tex]
Put the value into the formula
[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{1.55\times10^{-5}}[/tex]
[tex]T_{\dfrac{1}{2}}=44.719\times10^{3}\ s[/tex]
[tex]T_{\dfrac{1}{2}}=11.3\ hr[/tex]
(b). We need to calculate the value of N₀
Using formula of [tex]N_{0}[/tex]
[tex]N_{0}=\dfrac{3.70\times10^{6}}{\lambda}[/tex]
Put the value into the formula
[tex]N_{0}=\dfrac{3.70\times10^{6}}{1.55\times10^{-5}}[/tex]
[tex]N_{0}=2.38\times10^{11}\ nuclei[/tex]
(c). We need to calculate the sample's activity
Using formula of activity
[tex]R=R_{0}e^{-\lambda\times t}[/tex]
Put the value intyo the formula
[tex]R=10e^{-(1.55\times10^{-5}\times30\times3600)}[/tex]
[tex]R=1.87\ mCi[/tex]
Hence, (a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]
The half life is 11.3 hr.
(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]
(c). The sample's activity is 1.87 mCi.
How is ice more reflective than water??
Answer:
Because it has more texture and is solid. Its like glass
Explanation:
Answer:
Why is ice more reflective (has higher albedo) than liquid water? They're both the same substance (water). Is something quantum mechanical involved?
Explanation:
In fact ice is slightly less reflective than water. The reflectivity is related to the refractive index (in a rather complicated way) and the refractive index of ice is 1.31 while the refractive index of water is 1.33. The slightly lower refractive index of ice will cause a slightly lower reflectivity. In both cases the reflectivity is about 0.05 i.e. at an air/water or air/ice surface about 5% of the light is reflected.
The fastest human ever recorded was Usain Bolt at 43 km/h. If a white tail
deer can run 3 km in 3 minutes and 45 seconds, how many km/h faster would Usain Bolt need to run to catch a deer?
Please show work! Will mark brainliest!
If a car accelerates at a uniform 4.0 m/s, how long will it take to reach a speed of 36.0 m/s,
starting from rest?
Answer:
9s
Explanation:
v=u+at
36=0+4t
t=36-0/4
t=9s
The shortest path between two points is:
1) displacement
2) breadth
Answer:
the shortest path between two points is displacement..
Explanation:
Hope this helps you✌️✌️
Thanks .....
Follow for more help...
insta id :-ankitakki45..
What type of change is making water from H^2 and O^2 ?
A. chemical
B. physical
Answer: chemical
Explanation: To change from hydrogen to oxygen is a chemical change because if you change hydrogen to oxygen, it is still a chemical. The answer is chemical.
Answer:
chemical possibly
Explanation:
fact
A box is being pushed across the floor at a constant velocity with an
applied force of 30N, what is the magnitude of the frictional force acting
on this box?
Answer:
Magnitude of frictional force = 30 N
Explanation:
According to the second Newton's law, the net force exerted by an external agent on an object of mass m is:
Fn=m.a
The net force is the vector addition of each individual force. If the sum of all the forces acting on an object is zero, then the acceleration is zero. That means the object moves at a constant speed or is at rest.
When an object is pushed across a horizontal rough surface, there are two forces acting in the direction of the motion: The applied force and the frictional force.
If the applied force is greater than the frictional force, then the object moves at a constant positive acceleration. If the frictional force is greater than the applied force, then the object won't move at all (if it was at rest) or will start a deaccelerated motion (braking).
Finally, if both forces are equal, the object will move at a constant speed or remains at rest. Since the box is moving at a constant speed, we can conclude the frictional force equals the applied force:
Magnitude of frictional force = 30 N
All of the matter present at the beginning of a chemical reaction will still be present at the end of a chemical reaction, although possibly in a different form or substance. This is because of the...
A. Law of conversation of energy
B. Law Of Universal Gravitation
C. Law Of Conversation Of Mass
D. Ohms Law
Answer:
C. Law Of Conservation Of Mass
Explanation:
In this scenario, this would occur due and is explained by the Law of Conservation of Mass. This law basically states that the mass that exists during and after a chemical reaction must remain the same, assuming that the reaction is taking place in a closed environment where no loss of mass is occurring. This means that if the reaction is in a closed environment the mass should not change whatsoever even if it is not in the same form or substance as it was before the reaction occurred.
Multidimensional development means that:
A. development is static.
B. development occurs in a positive flow.
C. development sometimes goes in only one direction.
D. development occurs in many different areas at the same time.
Answer:
option D
Explanation:
this is because it occurs in many different dimensions, including biological, cognitive and socioemotional. this is also the answer on apex.
Answer D would be correct for a p e x
Choose the law that BEST explains the example:
Throwing a ball with more force to increase acceleration is an example of Newton’s
first law?
2nd law
third law
none of these
It’s really easy so plz help
Answer:false
Explanation:
2. The dust usually sticks ton TV iscreen because dust
A. Falls on the TV screen
B.Particles are metallic conductors
C.Is attracted by magnets in the TV screen
D. Is attracted
by static charges on the TV scien.
Answer:c
Explanation:
Which of these is a characteristic of climate
Answer:
No picture
Explanation:
An object has a mass of 20,000kg and a density of 4000kg/m? What is its
volume?
Which is the best estimate for the width of a typical adult hand?
Answer:
About 4-5in
Explanation:
POSSIBLE POINTS: 5
A student throws a ball upward with a force of 50.0 Newtons. The ball reaches a maximum height of 15.0 meters in 2 seconds and then returns back to
his hands. What is the direction of the acceleration at the top?
There is no acceleration at the top
O The acceleration is directed upwards away from the Earth
O The acceleration is directed downwards towards the Earth
O None of the above
Answer:
A
Explanation:
Given that a student throws a ball upward with a force of 50.0 Newtons. The ball reaches a maximum height of 15.0 meters in 2 seconds and then returns back to
his hands.
At maximum height which is the top, the velocity is equal to zero.
According to definition of acceleration, which says; the rate of change of velocity.
Since velocity equal zero, acceleration also will be equal to zero.
Therefore, there is no acceleration at the top.
How are velocity, wavelength, and frequency related
Answer:
The wave velocity and the wavelength are related to the wave's frequency and period by vw=λT or vw=fλ. The time for one complete wave cycle is the period T. The number of waves per unit time is the frequency ƒ. The wave frequency and the period are inversely related to one another.
Explanation: