Answer:
a) Vi = 137.2 m/s
b) h = 960.4 m
Explanation:
a)
In order to find the initial speed we will use first equation of motion:
Vf = Vi + gt
where,
Vf = Final velocity = 0 m/s (since ball stops at highest point)
Vi = Initial Velocity = ?
g = - 9.8 m/s² (negative sign for upward moyion)
t = time interval = 14 s
Therefore,
0 m/s = Vi + (-9.8 m/s²)(14 s)
<u>Vi = 137.2 m/s</u>
<u></u>
b)
Now, we use second equation of motion to find height (h):
h = Vi t + (1/2)gt²
h = (137.2 m/s)(14 s) + (1/2)(-9.8 m/s²)(14 s)²
h = 1920.8 m - 960.4 m
<u>h = 960.4 m</u>
Answer:
Explanation:
height of pole = 15 ft
height of man = 6 ft
Let the length of shadow is y .
According to the diagram
Let at any time the distance of man is x.
The two triangles are similar
15 y - 15 x = 6 y
9 y = 15 x
Differentiate with respect to time.
As given, dx/dt = 4 ft/s
ft/s
Answer:
B). Kelvin Scale
Explanation:
Kelvin scale is the absolute scale which is used to express temperature in English System
We have different temperature scales
1) Fahrenheit Scale
Generally use in British system of units
2) Celcius Scale
It is used to given temperature of different scales and its relation with kelvin
3) Rankine Scale
It is used in thermodynamic scales with large temperature range
Answer:
Impulse = 48 kg m/s
Gain in momentum = 48 kg m/s
Explanation:
Force (F) = 6N
Time (t) = 8
Mass (m) = 3 kg
Final velocity (v) = ?
Initial velocity (u) = 0 m/s
First, find acceleration
F = m * a
a = F / m
a = 6 / 3
a = 2 m/s^2
Now, find final velocity
v = u + a * t
v = 0 + 2 * 8
v = 16 m/s
Now, find impulse
Impulse = change in momentum
Impulse = final momentum - initial momentum
Impulse = m * v - m * u
Impulse = m ( v - u )
Impulse = 3 ( 16 - 0 )
Impulse = 48 kg m/s
Here, gain in momentum is same as impulse.
Pulse type of modulation is applied to radio-controlled toys, therefore the correct answer is option D.
<h3>What is the frequency?</h3>
It can be defined as the number of cycles completed per second. It is represented in hertz and inversely proportional to the wavelength.
Toys controlled by remote control operate by emitting infrared radiation. These infrared rays have a frequency of 34–48 kilo Hertz.
Different types of modulations, such as frequency and amplitude modulation for transmitting and receiving video and music, are employed for other reasons.
Thus, the Pulse-type of modulation is applied to radio-controlled toys, therefore the correct answer is option D.
Learn more about frequency from here
brainly.com/question/14316711
#SPJ1