Answer:
697 m
Explanation:
From the question above,
Note: Alice hears the splash of the rock in the well through the help of echo.
Applying,
v = 2x/t........................ Equation 1
Where v = speed of sound, x = depth of the well, t = time.
make x the subject of the formula in equation 1
x = vt/2................... Equation 2.
Given: v = 340 m/s, t = 4.1 s
Substitute these values into equation 2
x = 340(4.1)/2
x = 697 m.
Answer:
4) Isaac Newton was the first scientist to propose the idea that gravity increases distance between objects decrease
Explanation:
1 - Kepler may have inspired most of Newton's propositions, but there is no record of collaborating on the theory of universal gravitation.
2 - The universal gravitation theory resemble the works of other great scientists, but Newton was indeed the first to propose this idea of gravitation
3 - On the contrary, these scientists have shared concepts, with differences in accuracy that supersede each other to be accepted by the community (i.e: Einstein being at the forefront despite sharing some ideas with Newton)
Isn't it "gravity" this would makes sense because grvaity difines weight
Answer:
Magnesium and Bromine
Explanation:
I just took the test, and Magnesium has 7 electrons and Bromine has 2 valance electrons making the transfer a lot easier. In the first choice, Krypton already has 8 valance electrons therefore it cannot transfer or accept any more which rules it out as a possible answer. Calcium has 2 valance electrons and Potassium has 1 meaning it couldn't make a full shell of 8 and cannot make a ionic bond. Iodine has 7 electrons as well as Chlorine which wouldn't be the answer because it would have more than 8 valance electrons.
1.47x10^5 Joules
The gravitational potential energy will be the mass of the object, multiplied by the height upon which it can drop, multiplied by the local gravitational acceleration. And since it started at the top of a 60.0 meter hill, halfway will be at 30.0 meters. So
500 kg * 30.0 m * 9.8 m/s^2 = 147000 kg*m^2/s^ = 147000 Joules.
Using scientific notation and 3 significant figures gives 1.47x10^5 Joules.
