Answer:
A quasar is an extremely bright, distant object visible to radio telescopes.
Answer:
350 F to 100 F it take approx 87.33 min
Explanation:
given data
oven = 350◦F
cooling rack = 70◦F
time = 30 min
cake = 200◦F
solution
we apply here Newtons law of cooling
= -k(T-Ta)
= (T(t) -Ta)
= = -k(T-Ta)
-ky = -ky
T(t) -Ta = (To -Ta) T(t) = Ta+ (To -Ta)
put her value for time 30 min and T(t) = 200◦F and To =350◦F and Ta = 70◦F
so here
200 = 70 + ( 350 - 70 )
k = 0.025575
so here for T(t) = 100F
100 = 70 + ( 350 - 70 )
time = 87.33 min
so here 350 F to 100 F it take approx 87.33 min
Answer:
Explanation:
We are asked to find the acceleration of a box.
According to Newton's Second Law of Motion, force is the product of mass and acceleration.
The mass of the box is 5 kilograms. There are two forces applied: a 25 Newton force and a 50 Newton force, both applied right. Since they are applied in the same direction, we can add them.
- 25 N right + 50 N right = 75 N right.
Now we know 2 of the variables in the formula:
- F= 75 N or 75 kg*m/s²
- m= 5 kg
Substitute the values into the formula.
We are solving for a, so we must isolate the variable. It is being multiplied by 5 kilograms. The inverse operation of multiplication is division. Divide both sides by 5 kg.
The units of kilograms cancel.
The acceleration is in the same direction as the force, so the acceleration is <u> 15 meters per second squared to the right.</u>
Answer:
2.42 seconds
Explanation:
Assume that air resistance is negligible, use trigonometry to find the vertical component of the velocity by using trigonometry:
<span>31⋅<span>sin50</span>=23.7</span>
Where 31 <span>m<span>s<span>−1</span></span></span> is the hypotenuse and by using sin to get the opposite component (vertical velocity) of the trajectory.
Now comes the use of the formula:
v = u + at
where v is the final velocity (0 <span>m<span>s<span>−1</span></span></span>), u is the initial velocity (31 <span>m<span>s<span>−1</span></span></span> ), a is the acceleration of gravity (9.81 <span>m<span>s<span>−2</span></span></span>) and t is the time it takes to arrive at the top of the trajectory.
By making t as the subject:
<span>t=<span><span>v−u</span>a</span></span>
You can calculate the value of t:
<span><span><span>0−23.7</span><span>−9.81</span></span>=2.42</span> (to 3 significant figures)
Better way to see it:
<span><span><span>0−<span>(31⋅<span>sin50</span>)</span></span><span>−9.81</span></span>=2.421</span> (to 4 significant figures)
Note: You must remember that you are dealing with velocity, not speed . Since velocity is a vector quantity, you must select the direction at which values will be positive. In my example, I set my upward direction as the positive value while my downward vectors as negative value (a, acceleration, 9.81 <span>m<span>s<span>−1</span></span></span>).