Answer:
A. 19.6 m/s
B. 44.6 m
C. 5.0 s
D. -19.6 m/s
Explanation:
At the highest point, the stone's velocity is 0.
A. Given:
v = 0 m/s
t = 2 s
a = -9.8 m/s²
Find: v₀
v = at + v₀
0 = (-9.8)(2) + v₀
v₀ = 19.6 m/s
B. Given:
y₀ = 25 m
t = 2 s
v₀ = 19.6 m/s
a = -9.8 m/s²
Find: y
y = y₀ + v₀ t + ½ at²
y = 25 + (19.6)(2) + ½(-9.8)(2)²
y = 44.6 m
C. Given:
y₀ = 25 m
y = 0 m
v₀ = 19.6 m/s
a = -9.8 m/s²
Find: t
y = y₀ + v₀ t + ½ at²
0 = 25 + (19.6)t + ½(-9.8)t²
0 = 4.9t² − 19.6t − 25
t ≈ 5.0 s
D. Given:
v₀ = 19.6 m/s
a = -9.8 m/s²
t = 4 s
Find: v
v = at + v₀
v = (-9.8)(4) + 19.6
v = -19.6 m/s
The velocity is -19.6 m/s. If you want the speed, or magnitude of the velocity, take the absolute value: 19.6 m/s.
Hello!
I’m pretty sure your answer is D
Answer:11 km/s
Explanation:
Given
Escape velocity at the surface of earth is 11 km/s
Escape velocity is given by
Escape velocity at the surface of earth
--------------------1
If Escape velocity is three times and the radius is also the three times
i.e. 
The frequency f is related to the wavelength
by the equation
where v is the speed of the wave in the rope.
We can see from the formula that, if v is kept constant, smaller frequency means larger wavelength. So, the rope with frequency 2 Hz will have the longest wavelength.
Answer:
Nucleus A with 7 protons and 7 neutrons and Nucleus C with 7 protons and 5 neutrons are isotopes of the same elements
Explanation:
Isotopes are elements that have the same atomic structure but different molecular structure. An atom that has the same atomic number but different mass number are known to be isotopes.
The proton of an atom is the same as its atomic number while the sum of the proton and neutron is equal to its mass number.
According to the question, nuclei that has the same number of proton are isotopes of the same element. Therefore nuclei A and C with 7 protons each are isotopes of the same element since they have the same atomic number i.e number of proton = atomic number.
Their atomic masses of nuclei A and C are 14 and 12 respectively
