This year is 60 years since I learned this stuff, and one of the things I always remembered is the formula for the distance a dropped object falls:
D = 1/2 A T²
Distance = (1/2) (acceleration) (time²)
The reason I never forgot it is because it's SO useful SO often. You really should memorize it. And don't bury it too deep in your toolbox ... you'll be needing it again very soon. (In fact, if you had learned it the first time you saw it, you could have solved this problem on your own today.)
The problem doesn't tell us what planet this is happening on, so let's make it easy and just assume it's on Earth. Then the 'acceleration' is Earth gravity, and that's 9.8 m/s² .
In 5 seconds:
D = 1/2 A T²
D = (1/2) (9.8 m/s²) (5 sec)²
D = (4.9 m/s²) (25 sec²)
D = 122.5 meters
In 6 seconds:
D = 1/2 A T²
D = (1/2) (9.8 m/s²) (6 sec)²
D = (4.9 m/s²) (36 sec²)
D = 176 meters
Answer:
The repulsive electrostatic force between two of the protons is 14.4 N.
Explanation:
Given;
distance between the two protons, r = 4 x 10⁻¹⁵ m
charge of a proton, q = + 1.6 x 10⁻¹⁹ C
The repulsive electrostatic force between two of the protons is calculated by applying Coulomb's law;
Therefore, the repulsive electrostatic force between two of the protons is 14.4 N.
Answer:
B. 24.2 m/s
Explanation:
Given;
mass of the roller coaster, m = 450 kg
height of the roller coaster, h = 30 m
The maximum potential energy of the roller coaster due to its height is given by;
Therefore, the maximum speed of the roller coaster is 24.2 m/s.
ΔK = -2334.66J. The kinetic energy loss is -2334.66J.
This is an example of elastic collision which means that the two bodies remain united after the collision, as we know the amount of movement is preserved that is called conservation of momentum. So, we can write the equation as follow:
Where is the initial momentum and is the final momentum.
Substituting the values:
After the collision the bodies are united and move at the speed of 33.33 m/s.
To calculate the kinetic energy lost in the impact we only have to calculate the energy of each body before the impact and compare it with the energy of the whole after the impact.
ΔK =
ΔK =
Substituting the values:
ΔK =
ΔK =
ΔK =
ΔK =
ΔK =
ΔK =
Answer:
Magnetic field = 1.41 T
Explanation:
Magnetic field of solenoid, B = μnI
μ = 4π x 10⁻⁷N/A²
Number of turns per meter,
Current, i = 18.2 A
B = μnI = 4π x 10⁻⁷ x 6.15 x 10⁴ x 18.2 = 1.41 T
Magnetic field = 1.41 T