Answer:
7.2 x 10⁻⁶N
Explanation:
Given parameters:
Mass of Venus = 4.87 x 10²⁴kg
Radius = 6.05 x 10⁶km = 6.05 x 10⁹m
Mass of person = 81kg
Unknown:
Gravitational force = ?
Solution:
To solve this problem, we use the Newtons law of universal gravitation:
Fg =
G is the universal gravitation constant = 6.67 x 10⁻¹¹
Fg =
Fg = 7.2 x 10⁻⁶N
Answer:
a) 431 Hz
b) 429 Hz
c) 403 Hz
Explanation:
The frequency you heard is calculated using the relation
f = f(s) / [1 - (v(s)/v) ]
f = 400 / [1 - 25/343]
f = 400 / (1 - 0.0729)
f = 400 / 0.9271
f = 431.5 Hz
The frequency your friend starts hearing is
f = f(s) * [1 + (v(s)/v) ]
f = 400 * [1 + 25/343]
f = 400 * (1 + 0.0729)
f = 400 * 1.0729
f = 429.2 Hz
when you're next to each other and you are hearing 3 beats per second. The frequency you're singing is 400 + 3 Hz
403 Hz
Answer:
This is an incomplete question. The complete question is --
An individual white LED (light-emitting diode) has an efficiency of 20% and uses 1.0 W of electric power.
How many LEDs must be combined into one light source to give a total of 3.8W of visible-light output (comparable to the light output of a 100W incandescent bulb)?
And the answer is --
19 LEDs
Explanation:
The full form of LED is Light emitting diode.
It is given that the efficiency of the LED bulb is 20 %
1 LED uses power = 1 W
So the output power of 1 LED = 0.2 W
We need to find the power required to give a 3.8 W light.
Power required for 3.8 W = Number of LEDs required = (total required power / power required for 1 LED )
= 3.8 / 0.2
= 19
Therefore, the number of LEDs required is 19.