Answer:
F = 1.6*10⁴ N
Explanation:
Given distance x = 0.15m, mass m = 1200kg, velocity v = 2m/s.
Unknown: force F
Force is given by Newton's law:
(1) 
The average force to stop an object from a velocity will be the same force necessary to accelerate an object from rest to the same velocity.
The distance for an object starting from rest for a constant acceleration is given by:
(2) 
The velocity for an object starting from rest for a constant acceleration:
(3) 
Using equation 2 and 3 to eliminate time t:
(4) 
Solving equation 4 for the acceleration a:
(5) 
Using equation1 to solve for the force F:
(6) 
The relation between the angle of incidence and the angle of refraction is known as Snell's Law. Since the light travels with different speed in different media, the direction of the ray of light will change when it crosses the boundary between the two media
Sounds are created when something vibrates (shakes back and forth), sending waves of vibrations into the ears of the listener. When a bell is struck, the metal vibrates. The vibrations travel through the air as sound waves.
hope this helps
Answer:
The rocket has to be launched 8 m from the hoop
Explanation:
Let's analyze this problem, the rocket is on a car that moves horizontally, so the rocket also has the same speed as the car; The initial horizontal rocket speed is (v₀ₓ = 3.0 m/s).
On the other hand, when starting the engines we have a vertical force, which creates an acceleration in the vertical axis, let's use Newton's second law to find this vertical acceleration
F -W = m a
a = (F-mg) / m
a = F/m -g
a = 7.0/0.500 - 9.8
a = 4.2 m/s²
We see that we have a positive acceleration and that is what we are going to use in the parabolic motion equations
Let's look for the time it takes for the rocket to reach the height (y = 15m) of the hoop, when the rocket fires its initial vertical velocity is zero (I'm going = 0)
y = 
t + ½ a t²
y = 0 + ½ a t²
t = √ 2y/a
t = √( 2 15 / 4.2)
t = 2.67 s
This time is also the one that takes in the horizontal movement, let's calculate how far it travels
x = v₀ₓ t
x = 3 2.67
x = 8 m
The rocket has to be launched 8 m from the hoop
Answer:
v = 2.974
Explanation:
Perhaps the formula should be
v = √(2*g*d (sin(θ) - uk*cos(θ) ) This is a bit easier to read.
v = √(2* 9.80*0.725(0.707 - 0.12*0.707) ) Substitute values. Find 2*g*d
v = √14.21 * (0.707 - 0.0849) Figure out Sin(θ) - uk cos(θ)
v = √14.21 * (0.6222)
v = √8.8422 Take the square root of the value
v = 2.974
