Answer:
because concave mirror is used in them.
hope it helps.
239.7
To figure it out, add 273 to the temp in Celsius and you have temp in Kelvin!!
Litmus paper and phenolphthalein
Answer:
vx = 65 yd/3 sec = 21.7 yd/sec since horizontal speed is constant
vy = g t = (32 / 3) yd/sec^2 * 1.5 sec = 16 yd/sec where 32/3 is the acceleration due to gravity in yds / sec^2 and 1.5 is the time to travel each way in the vertical direction
V = (vx^2 + vy^2)^1/2 = (21.7^2 + 16^2)^1/2 = 27 yd/sec
tan theta = vy/vx = 16 / 21.7 = .737 theta = 36.4 deg
You can check using the range formula:
R = v^2 sin (2 theta) / g = 27^2 * .955 / (32 / 3) = 65.3 yds
The difference from 65 yds may be rounding error.
Answer:
a
t = 1.235 s
b
![h_{max} = 2.55 \ m](https://tex.z-dn.net/?f=h_%7Bmax%7D%20%3D%20%202.55%20%5C%20m)
c
![v = -7.10 m/s](https://tex.z-dn.net/?f=v%20%20%3D%20%20-7.10%20m%2Fs)
Explanation:
From the question we are told that
The initial velocity is ![u = 5.0 \ m/s](https://tex.z-dn.net/?f=u%20%20%3D%205.0%20%5C%20%20m%2Fs)
The take of height is ![h = -1.30 \ m](https://tex.z-dn.net/?f=h%20%20%3D%20%20-1.30%20%5C%20%20m)
The negative sign show that the height is on the negative y-axis when the take off point is consider as the origin
Generally from the kinematic equation we have that
![s = ut + \frac{1}{2}at^2](https://tex.z-dn.net/?f=s%20%3D%20%20ut%20%2B%20%20%5Cfrac%7B1%7D%7B2%7Dat%5E2)
=> ![-1.30 = 5.0 t + \frac{1}{2} (-9.8)t^2](https://tex.z-dn.net/?f=-1.30%20%3D%20%205.0%20t%20%2B%20%20%5Cfrac%7B1%7D%7B2%7D%20%28-9.8%29t%5E2)
Here g is negative given that the swimmers jump motion is against gravity
![4.9t^2 - 5t - 1.30](https://tex.z-dn.net/?f=4.9t%5E2%20-%20%205t%20%20-%20%201.30)
solving using quadratic formula we obtain that
t = 1.235 s
Generally the highest point is mathematically evaluated as
![h_{max} = \frac{v^2 - u^2 }{2 * (-g) }](https://tex.z-dn.net/?f=h_%7Bmax%7D%20%3D%20%20%5Cfrac%7Bv%5E2%20%20-%20%20u%5E2%20%7D%7B2%20%2A%20%28-g%29%20%7D)
Here v = 0 m/s since the velocity at the highest point is 0
![h_{max} = \frac{0^2 - 5^2 }{2 * (-9.8) }](https://tex.z-dn.net/?f=h_%7Bmax%7D%20%3D%20%20%5Cfrac%7B0%5E2%20%20-%20%205%5E2%20%7D%7B2%20%2A%20%28-9.8%29%20%7D)
![h_{max} = 2.55 \ m](https://tex.z-dn.net/?f=h_%7Bmax%7D%20%3D%20%202.55%20%5C%20m)
Generally her velocity when the feet hits the water is mathematically evaluated from kinematic equation as
![v = \pm \sqrt{ u^2 + 2 (-g) * (-h)}](https://tex.z-dn.net/?f=v%20%20%3D%20%20%5Cpm%20%5Csqrt%7B%20u%5E2%20%20%2B%202%20%28-g%29%20%2A%20%20%28-h%29%7D)
![v = -7.10 m/s](https://tex.z-dn.net/?f=v%20%20%3D%20%20-7.10%20m%2Fs)
The negative value of the velocity is selected because the velocity is on the negative y-axis