Answer:
280 N
Explanation:
Applying Newton's third second law of motion,
F = m(v-u)/t................... Equation 1
Where F = Magnitude of the average force on the ball during contact, v = final velocity of the ball, u = initial velocity of the ball, t = time of contact of the ball and the wall.
Note: Let the direction of the initial velocity of the ball be positive
Given: m = 4 kg, u = 3.0 m/s, v = -4.0 m/s (bounce off), t = 0.1 s
Substitute into equation 1
F = 4(-4-3)/0.1
F = 4(-7)/0.1
F = -28/0.1
F = -280 N.
Note: The negative sign tells that the force on the ball act in opposite direction to the initial motion of the ball
Given:
distance from the projector lens to the image, di
projector lens focal length, f
distance from the transparency to the projector lens, do
thin lens equation: 1/f = 1/di + 1/do
do = 4 inches
di = 8 feet
convert feet to inches, for uniformity.
1 foot = 12 inches
8 feet * 12 inches/ft = 96 inches
1/f = 1/96 inches + 1/4 inches
Adding fractions, denominator must be the same.
1/f = (1/96 * 1/1) + (1/4 * 24/24)
1/f = 1/96 + 24/96
1/f = 25/96
to find the value of f, do cross multiplication
1*96 = f * 25
96 = 25f
96/25 = f
3.84 = f
The focal length of the project lens is 3.84 inches
It is the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree).
Answer: 750Kg
Explanation:
Recall that force is the product of the mass M, of an object moving at a uniform acceleration.
i.e Force = Mass x Acceleration
In this case, Mass = ?
Force = 3.00 x 10^3 N = (3.00 x 1000N)
= 3000N
Uniform acceleration = 4.00m/s^2
Force = Mass x Acceleration
3000N = Mass x 4.00m/s^2
Mass = (3000N/4.00m/s^2)
Mass = 750Kg (The SI unit of mass is kilograms)
Thus, the mass of the car is 750Kg
<span>25,000 miles per hour
hope that this helps</span>