Answer:
The car strikes the tree with a final speed of 4.165 m/s
The acceleration need to be of -5.19 m/seg2 to avoid collision by 0.5m
Explanation:
First we need to calculate the initial speed 
Once we have the initial speed, we can isolate the final speed from following equation:
Then we can calculate the aceleration where the car stops 0.5 m before striking the tree.
To do that, we replace 62 m in the first formula, as follows:

We shall convert all of the densities to lbs/gal, so the product of
BTU/lbs and lbs/gal gives us the basis of comparison, which was "ratio of energy to volume".
grams / ml x 1 lbs/454 grams → 1 lbs/ 454 ml
1 lbs/454 ml x 3785.41 ml/gal → 3785.41 lbs/454gal
Conversion of g/ml = 8.34 lbs/gal
Looking at each fuel:
Kerosene:
18,500 x (8.34 x 0.82) = 126,517 BTU/gal
Gasoline:
20,900 x (8.34 x 0.737) = 128,463 BTU/gal
Ethanol:
11,500 x (8.34 x 0.789) = 75,673 BTU/gal
Hydrogen:
61,000 x (8.34 x 0.071) = 36,120 BTU/gal
The best fuel in terms of energy to volume ratio is Gasoline.
Gallons required:
BTU needed / BTU per gallon
= 85.2 x 10⁹ / 128,463
= 6.6 x 10⁵ gallons
Answer:

Explanation:
The equation for work is:

We can substitute the given values into the equation:

Where power<span> P is in watts, voltage V is in volts and current I is in amperes (DC).</span>Power Formula<span> 2 – Mechanical </span>power equation<span>: </span>Power<span> P = E ⁄ t where </span>power<span> P is in watts, </span>Power<span> P = work / time (W ⁄ t). Energy E is in joules, and time t is in seconds.</span>
Answer:
35.28m/s; 63.50m
Explanation:
<u>Given the following data;</u>
Time, t = 3.6 secs
Since it's a free fall, acceleration due to gravity = 9.8m/s²
Initial velocity, u = 0
To find the final velocity, we would use the first equation of motion;
Substituting into the equation, we have;
V = 35.28m/s
Therefore, the final velocity of the penny is 35.28m/s.
To find the height, we would use the second equation of motion;

Substituting the values into the equation;



S = 63.50m
Therefore, the height of the tower is 63.50m.