Answer: The correct answers are (A) and (C).
Explanation:
The expression from electrostatic force is as follows;
Here, F is the electrostatic force, k is constant, r is the distance between the charges and 
are the charges.
The electrostatic force follows inverse square law. It is inversely proportional to the square of the distance between the charges. It is directly proportional to the product of the charges.
Like charges repel each other. There is a force of electrostatic repulsion between the like charges. Unlike charges attract each other. There is a force of electrostatic attraction between unlike charges.
The charges are induced on the neutral object when it is placed nearby the charged object without actually touching it.
Therefore, the true statements from the given options are as follows;
Like charges repel.
Unlike charges attract.
Answer:
18.1347 m/s
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration
g = Acceleration due to gravity = 9.81 m/s² = a
Total height the ball falls is 2.4619+14.3 = 16.7619 m
The speed at which the stone reaches the ground is 18.1347 m/s
Answer:
a) 51.8 cm³
b) kg/m³ is a dimension of density (mass/volume). The regular unitys for volume are m³, cm³, L, gallons.
Explanation:
a) The density of pure gold is 19.3 g/cm³. When put in water, the piece of gold will occupy a volume, so that the volume of water will be displaced. To know the volume, we must divide the mass for the density (mass must be in grams because of the units of the density)
V = 1000/19.3
V = 51.8 cm³
Answer: 0.85 meters (with and without sigfigs)
Explanation: To find the wavelength, you just have to switch around the equation for wave speed: v (wave speed) = λ (wavelength)*f (frequency) so λ (wavelength) = v (wave speed)/f (frequency). You don't have the wave speed but you can calculate it. Since wave speed is measured in meters/second or m/s, you just have to divide the amount of meters you were given by the amount of seconds. You will get 340 m/s. Next, you have to plug the values into the equation: λ (wavelength) = 340 m/s (wave speed)/400 Hz (frequency). The answer is 0.85 meters (seconds cancel) and has the correct number of significant figures.
