Answer:
The car stops in 7.78s and does not spare the child.
Explanation:
In order to know if the car stops before the distance to the child, you take into account the following equation:
(1)
vo: initial speed of the car = 45km/h
a: deceleration of the car = 2 m/s^2
t: time
xo: initial distance to the child = 25m
x: final distance to the child = 0m
It is necessary that the solution of the equation (1) for time t are real.
You first convert the initial speed to m/s, then replace the values of the parameters and solve the quadratic polynomial for t:
You take the first value t1 because it has physical meaning.
The solution for t is real, then, the car stops in 7.78s and does not spare the child.
The formula used to find potential energy is <em>P.E. = M * G * H</em> (P.E. is potential energy, M is mass, G is gravitational pull, and H is height). So the answer to your question is <em>5 * 9.8 * 2</em>, which equals 98.
Answer:
Explanation:
From the second law of Newton movement laws, we have:
, and we know that a is the acceleration, which definition is:
, so:
The next step is separate variables and integrate (the limits are at this way because at t=0 the block was at rest (v=0):
(This is the indefinite integral), the definite one is:
Answer:
11 kilometers (7 miles) per second, or over 40,000 kilometers per hour (25,000 miles per hour)
Explanation:
1 mol of oxygen molecules = 2 * 16 = 32 grams.
x mol of oxygen = 16 grams
1/x = 32/16 Cross multiply
16 = 32x Divide by 32
16/32 = x
x = 1/2 mol
1 mol of anything has 6.02 * 10^23 somethings (molecules in this case).
1/2 mol = 6.02 *10^23 / 2
1/2 mol = 3.01 * 10^23 molecules <<<< answer
