Answer:
Useful Output = 35 J
Explanation:
The useful energy output of the car must be equal to the difference between the total input energy supplied to the car and the energy wasted by the car:
Useful Output = Total Input - Waste
where,
Total Input = 120 J
Waste = 85 J
Therefore,
Useful Output = 120 J - 85 J
<u>Useful Output = 35 J</u>
Answer:
The frequency heard by the motorist is 4313.2 Hz.
Explanation:
let f1 be the frequency emited by the police car and f2 be the frequency heard by the motorist, let v1 be the speed of the police car and v2 be the speed of the motorist and v = 343 m/s be the speed of sound.
because the police car is moving towards the motorist at a higher speed, then the motorist will hear a increasing frequency and according to Dopper effect, that frequency is given by:
f1 = [(v + v2/(v - v1))]×(f2)
= [( 343 + 30)/(343 - 36)]×(3550)
= 4313.2 Hz
Therefore, the frequency heard by the motorist is 4313.2 Hz.
Answer:
B. 2
Explanation:
The reaction expression is given as:
_S + 3O₂ → 2SO₃
Now let us balanced the expression;
On the product side we have 2 moles of S
On the reactant side we should have 2moles of S
So, we put the coefficient 2 to balance the expression;
We have 6 moles oxygen on both sides
Answer: boy B, same
Explanation:
Given
One boy trips off the waterslide while the other starts sliding down
As there is no horizontal velocity, both boys have to travel the same vertical distance.
Their starting vertical velocity is zero and they need to travel the same vertical distance. Therefore, both boys splash water with the same velocity.
The time taken by boy B is more than boy A as boy B will travel some horizontal distance due to slide which will increase its time to reach the bottom.
Answer:
The dog catches up with the man 6.1714m later.
Explanation:
The first thing to take into account is the speed formula. It is 
, where v is speed, d is distance and t is time. From this formula, we can get the distance formula by finding d, it is 
Now, the distance equation for the man would be:
The distance equation for the dog would be obtained by the same way with just a little detail. The dog takes off running 1.8s after the man did. So, in the equation we must subtract 1.8 from t.
For a better understanding, at t=1.8 the dog must be in d=0. Let's verify:
Now, for finding how far they have each traveled when the dog catches up with the man we must match the equations of each one.
The result obtained previously means that the dog catches up with the man 3.8571s after the man started running.
That value is used in the man's distance equation.
Finally, the dog catches up with the man 6.1714m later.
