Answer:
1,700feet
Explanation:
If an object in free fall travels a distance s that is directly proportional to the square of the time t, this can be represented mathematically as;
S = kt²where;
k is the proportionality constant
K = s/t²
s1/t1²= s2/t2²= Sn/tn²= k for values of the distance and time. Using the formula
s1/t1² = s2/t2² where;
s1 is the falling distance in time t1 s2 is the falling distance in time t2
Given s1 = 1088feet, t1 = 8secs, s2 = ? t2 = 10secs
Substituting this value in the formula to get s2, we have;
1088/8²= s2/10²
64s2= 108800
s2 = 108800/64
s2 = 1,700feet
This means the object will fall a distance of 1,700feet in 10seconds
C.
The train first sped up, giving it a positive acceleration in the beginning. This eliminates D since that choice states that it begins with a negative acceleration. This also eliminates B since that choice states that the train only had a negation acceleration.
Next, the train slows down, giving it a negative acceleration. We’re looking for the answer choice that starts with a positive acceleration and ends with a negative one. This makes C the correct answer. Hope this helps!
Answer:0.0909 kJ/K
Explanation:
Given
Temperature of hot Reservoir 
Temperature of cold Reservoir 
Heat of 100 kJ is transferred form hot reservoir to cold reservoir
Hot Reservoir is Rejecting heat therefore 
Heat is added to Reservoir therefore 
Entropy change for system
As entropy change is Positive therefore entropy Principle is satisfied
Answer:
4.17 m/s²
Explanation:
We are told the reaction time is 0.2 s. Now, during this reaction time the car is going to travel an additional distance of
: x = u × t = 40 × 0.2 = 8 m
where u is the initial velocity of the car which is 40.0 m/s.
We are told that he had 200 m to stop before applying brakes. Thus, after applying brakes, he now has a distance to cover of; s = 200 - 8 = 192 m
Since vehicle is coming to rest acceleration would be negative, thus using Newton's equation of motion, we have;
v
² = u² - 2as
v = 0 m/s since it's coming to rest
u = 40 m/s
s = 192 m
Thus;
0² = 40² - 2(a)(192)
0² = 1600 - 384a
a = 1600/384
a = 4.17 m/s²
Sound intensity = 1/(r^2)
That is Sound intensity is indirectly proportional to the distance. Therefore, sound becomes 9 times less intense.
