Answer:
83.67 m/s
Explanation:
Set up a calculation to convert units of measure to what you need.
You have km/s and you need m/s.
4.08km 1000 m 83.67m
----------- X ---------- = --------------- the km will cancel out and you are left
12.0 s 1 km s with m/s
That's false.
The definition of momentum is (mass) x (speed), so they must be multiplied.
"20,000 kg-m/s" has the correct units resulting from multiplication, but the number could only be the result of division.
The Pacific is loosely shaped like a triangle, opening widely to the south but barely at all to the north, while the Atlantic is shaped like an hourglass with the choke point located very loosely at the equator (somewhat south of it in the west).
Answer:
just before landing the ground
Explanation:
Let the velocity of projection is u and the angle of projection is 30°.
Let T is the time of flight and R is the horizontal distance traveled. As there is no force acting in horizontal direction, so the horizontal velocity remains constant. Let the particle hits the ground with velocity v.
initial horizontal component of velocity, ux = u Cos 30
initial vertical component of velocity, uy = u Sin 30
Time of flight is given by
![T = \frac{2u Sin\theta }{g}](https://tex.z-dn.net/?f=T%20%3D%20%5Cfrac%7B2u%20Sin%5Ctheta%20%7D%7Bg%7D)
Final horizontal component of velocity, vx = ux = u Cos 30
Let vy is teh final vertical component of velocity.
Use first equation of motion
vy = uy - gT
![v_{y}=u_{y}- g \times \frac{2u Sin\theta }{g}](https://tex.z-dn.net/?f=v_%7By%7D%3Du_%7By%7D-%20g%20%5Ctimes%20%5Cfrac%7B2u%20Sin%5Ctheta%20%7D%7Bg%7D)
![v_{y}=u Sin 30 - 2u Sin 30](https://tex.z-dn.net/?f=v_%7By%7D%3Du%20Sin%2030%20-%202u%20Sin%2030)
vy = - u Sin 30
The magnitude of final velocity is given by
![v = \sqrt{v_{x}^{2}+v_{y}^{2}}](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%7Bv_%7Bx%7D%5E%7B2%7D%2Bv_%7By%7D%5E%7B2%7D%7D)
![v = \sqrt{\left (uCos 30 \right )^{2}+\left (uSin 30 \right )^{2}}](https://tex.z-dn.net/?f=v%20%3D%20%5Csqrt%7B%5Cleft%20%28uCos%2030%20%20%5Cright%20%29%5E%7B2%7D%2B%5Cleft%20%28uSin%2030%20%20%5Cright%20%29%5E%7B2%7D%7D)
v = u
Thus, the velocity is same as it just reaches the ground.
Answer:
12552 J or 3000 calories
Explanation:
Q = m × c × ∆T
Where;
Q = amount of heat energy (J)
m = mass of water (g)
c = specific heat capacity (4.184 J/g°C)
∆T = change in temperature
For 50mL of water, there are 50g, hence, m = 50g, c = 4.184 J/g°C, initial temperature = 0°C, final temperature = 60°C.
Q = m × c × ∆T
Q = 50 × 4.184 × (60 - 0)
Q = 209.2 × 60
Q = 12552 J
Hence, the amount of heat energy used to heat the water is 12552 J or 3000 calories