Whenever an object is in projectile motion, that is, it has 2-dimensional motion in the x and y axis, the resultant force on the object is in the y-direction.
This is because once the object has been projected, or the ball has been kicked in this case, there is no longer a force being applied on it in the x-direction. The air resistance is also neglected so the ball's final velocity in the x-direction is equal to its initial velocity in the x-direction.
However, the force of gravity cannot be neglected and causes the ball to come downwards. Therefore, after the ball has been projected, the net force on the ball is downwards, due to gravity.
Well at the fourth half-life it would be 6.25% so if you continue calculating the answer would be B.
Answer:
The wavelength of wave is 7.5 meter.
Given:
Speed of wave = 1500 
Frequency of wave = 200 Hz
To find:
Wavelength of wave = ?
Formula used:
Where 
= wavelength of the wave
v = speed of wave
n = frequency of wave
Solution:
Wavelength of wave is given by,
Where = wavelength of the wave
v = speed of wave
n = frequency of wave
= 7.5 m
The wavelength of wave is 7.5 meter.
Complete question:
Resistor is made of a very thin metal wire that is 3.2 mm long, with a diameter of 0.4 mm. What is the electric field inside this metal resistor? If the potential difference due to electric field between the two ends of the resistor is 10 V.
Answer:
The electric field inside this metal resistor is 3125 V/m
Explanation:
Given;
length of the wire, L = 3.2 mm = 3.2 x 10⁻³ m
diameter of the wire, d = 0.4 mm = 0.4 x 10⁻³ m
the potential difference due to electric field between the two ends of the resistor, V = 10 V
The electric field inside this metal resistor is given by;
ΔV = EL
where;
ΔV is change in electric potential
E = ΔV / L
E = 10 / (3.2 x 10⁻³ )
E = 3125 V/m
Therefore, the electric field inside this metal resistor is 3125 V/m
Given :
The focal length of a concave mirror is 18 cm.
To Find :
The radius of curvature of the concave mirror.
Solution :
We know,
Therefore, the radius of curvature of concave mirror is 36 cm.
Hence, this is the required solution.
