Answer:
20 m/s
30 m/s
Explanation:
Given:
v₀ = -10 m/s
a = -9.8 m/s²
When t = 1 s:
v = v₀ + at
v = (-10 m/s) + (-9.8 m/s²) (1 s)
v = -19.8 m/s
When t = 2 s:
v = v₀ + at
v = (-10 m/s) + (-9.8 m/s²) (2 s)
v = -29.6 m/s
Rounded to one significant figures, the speed of the ball at 1 s and 2 s is 20 m/s and 30 m/s, respectively.
Explanation:
Given that,
The dimensions of the largest building in the world is 632 m long, 710 yards wide, and 112 ft high. It basically forms a cuboid. The volume of a cuboidal shape is given by :
Since,
1 meter = 3.28084 feet
632 m = 2073.49 feet
1 yard= 3 feet
710 yards = 2130 feet
V = lbh
![V=2073.49 \ ft\times 2130\ ft\times 112\ ft](https://tex.z-dn.net/?f=V%3D2073.49%20%5C%20ft%5Ctimes%202130%5C%20ft%5Ctimes%20112%5C%20ft)
![V=494651774.4\ ft^3](https://tex.z-dn.net/?f=V%3D494651774.4%5C%20ft%5E3)
![V=4.94\times 10^8\ ft^3](https://tex.z-dn.net/?f=V%3D4.94%5Ctimes%2010%5E8%5C%20ft%5E3)
Also,
![V=(4.94\times 10^8\ ft^3)(\dfrac{1\ m}{3.281})^3](https://tex.z-dn.net/?f=V%3D%284.94%5Ctimes%2010%5E8%5C%20ft%5E3%29%28%5Cdfrac%7B1%5C%20m%7D%7B3.281%7D%29%5E3)
![V=1.39\times 10^7\ m^3](https://tex.z-dn.net/?f=V%3D1.39%5Ctimes%2010%5E7%5C%20m%5E3)
Hence, this is the required solution.
Spring potential energy:
E = 0.5 * k * x²
k spring constant
x spring compression
x = √(2 * E / k) = 0.7
Okay so don't quote me on this but I believe the answer is A) I'm saying this because B and C make no sense. and you can't change the mass of something without changing it totally.
Answer:
Explanation:
Given a school bus.
Let say initially the school bus is traveling with speed "v"
Let assume mass of school bus is "m"
Then, the initial kinetic energy is
K.E_initial = ½mv²
Now, if the initial velocity is tripled,
Then, the new velocity is
v_new = 3v.
Note: the mass of the school does not change it is constant
Then, new kinetic energy is
K.E_new = ½m(v_new)²
v_new = 3v
Then,
K.E_new = ½m(3v)²
K.E_new = ½m × 9v²
K.E_new = 9 × ½mv²
Since K.E = ½mv²
Then,
K.E_new = 9 × K.E
So, the new kinetic energy will be 9 times the initial kinetic energy.
So, option D is correct
D. It will be nine times greater.