To solve this problem we use the general kinetic equations.
We need to know the time it takes for the car to reach 130 meters.
In this way we have to:
Where
= initial position
= initial velocity
= acceleration
= time
= position as a function of time
.
We use the quadratic formula to solve the equation.
t = 6.63 s and t = -17.1 s
We take the positive solution. This means that the car takes 6.63 s to reach 130 meters.
Then we use the following equation to find the final velocity:
Where:
= final speed
The final speed of the car is 27.25 m/s
Answer: 93ft
Explanation: Martha's eyesight make an angle with the fence, this is solved as a triangle problem.
We first convert all the dimensions to inches using the fact that 12 inches make 1 ft.
To solve for the angle
Tan § = 18/48 = 0.375
§ = tan^-1 of 0.375 = 20.55°
This same angle elevates to the edge of the building
Tan 20.55 = 399/x
x = 399/tan 20.55
x = 1040 inches
Height of building = x + height of fence
Height of building = 1040 + 78 = 1118 inches
Converting back to ft it becomes
1118/12 = 93 ft 2 inches
Approximately 93ft
Answer:
<em>The rebound speed of the mass 2m is v/2</em>
Explanation:
I will designate the two masses as body A and body B.
mass of body A = m
mass of body B = 2m
velocity of body A = v
velocity of body B = -v since they both move in opposite direction
final speed of mass A = 2v
final speed of body B = ?
The equation of conservation of momentum for this system is
mv - 2mv = -2mv + x
where x is the final momentum of the mass B
x = mv - 2mv + 2mv
x = mv
to get the speed, we divide the momentum by the mass of mass B
x/2m = v = mv/2m
speed of mass B = <em>v/2</em>
Answer:
Explanation:
0°Κ = -273.15°C = -459.67 °F
1 °K = 9/5 °F
a) 75.6 - 273.15 = -197.55 °C
b) -459.67 + 75.6(9/5) = -323.59 °F