Answer: The final velocity is 33.78 mi/h, so the driver did reduced his speed enough.
Explanation: The kinetic energy of an object can be calculated as:
K = (1/2)m*v^2
We know that the mass of the car is m=1100kg
and the initial velocity is 22m/s
The initial kinetic energy is:
K = (1/2)*1100*(22)^2 = 266,200 joules.
Now, if the kinetic energy decreases by 1.4x10^5 J, the new kinetic energy is:
K = 266,200j - 140,000j = 126,200j
So we now can find the new velocity in m/s.
126,200 = (1/2)*1100*v^2
126,200*2/1100 = v^2
229.45 = v^2
v = (229.45)^(1/2) = 15.1 m/s
We know that the limit is 35 mi/h, so we need to transform our result into miles per hour.
We know that in one hour, there are 3600 seconds, so the velocity per hour is:
15.1*3600 m/h = 54,360 m/h
and we know that one mile is 1609.34 meters, so we need to divide by 1609.34.
v = (54,360/1609.34) mi/h = 33.78 mi/h
this is less than the speed limit, so the driver reduced his speed enough.
After losing kinetic energy, the car's final velocity was approximately 18.99 m/s, exceeding the exit's speed limit of 15.64 m/s, hence the driver did not reduce their speed adequately.
Explanation:To determine whether the driver reduced their speed enough when exiting the highway, we must calculate the car's speed after its kinetic energy decreases by 1.4×105J. The initial kinetic energy (KE) of the 1100-kg car traveling at 22 m/s can be calculated using the equation KE = ½ mv². Plugging in the values, we can find the initial kinetic energy:
KEinitial = ½ (1100 kg)(22 m/s)² = 5.28×105J
After losing 1.4×105J of energy, the remaining kinetic energy will be:
KEfinal = KEinitial - 1.4×105J = (5.28 - 1.4)×105J = 3.88×105J
We can solve for the final velocity (vfinal) using the remaining kinetic energy:
½ (1100 kg)vfinal² = 3.88×105J
vfinal = √((2×3.88×105J) / 1100 kg)
vfinal ≈ 18.99 m/s
To compare to the speed limit, we convert 35 mi/h to meters per second:
35 mi/h × 0.44704 (conversion factor) = 15.64 m/s
Since the final velocity of the car is 18.99 m/s, which is greater than the exit's speed limit of 15.64 m/s, the driver did not reduce their speed enough.
If a force of 10 n is applied to an object with a mass of 1kg the object will accelerate at