When you see an object that is not a light source, you are seeing light waves __

Suppose a skydiver jumps out of a plane at 15,000 meters above the ground. It takes him 2.0 seconds to pull the cord to deploy t

Evgesh-ka [11]

Answer:

The time he can wait to pull the cord is 41.3 s

Explanation:

The equation for the height of the skydiver at a time "t" is as follows:

y = y0 + v0 · t + 1/2 · g · t²

Where:

y = height at time "t".

y0 = initial height.

v0 = initial velocity.

t = time.

g = acceleration due to gravity (-9.8 m/s² considering the upward direction as positive).

First, let´s calculate how much time will it take for the skydiver to hit the ground if he doesn´t activate the parachute.

When he reaches the ground, the height will be 0 (placing the origin of the frame of reference on the ground). Then:

y = y0 + v0 · t + 1/2 · g · t²

0 m = 15000 m + 0 m/s · t - 1/2 · 9.8 m/s² · t²

0 m = 15000 m - 4.9 m/s² · t²

-15000 m / -4.9 m/s² = t²

t = 55.3 s

Then, if it takes 4.0 s for the parachute to be fully deployed and the parachute has to be fully deployed 10.0 s before reaching the ground, the skydiver has to pull the cord 14.0 s before reaching the ground. Then, the time he can wait before pulling the cord is (55.3 s - 14.0 s) 41.3 s.

6 0

3 years ago

A positive charge is placed in an electric field that points west. What direction is the force on the positive particle? I think

Kisachek [45]

Right. You are true. The direction of the electric field is defined to be
the direction of the force on a small positive charge placed in the field.

3 0

3 years ago

What is the equivalent resistance of a circuit that contains four 75.0 resistors connected in parallel with a 100.0 V battery?

zhannawk [14.2K]

To get the total resistance in a parallel circuit, you need to remember that unlike in a series, you do not just merely add the resistances. You need to get the reciprocal first of each resistance and add them together.

$\frac{1}{R_{T}} = \frac{1}{R_{1}}+\frac{1}{R_{2}}+\frac{1}{R_{3}}... +\frac{1}{R_{n}}$

After adding them, you will get the reciprocal again and then compute for the value. The problem says that there are 4 resistors in the circuit that have a resistance of 75.

$\frac{1}{R_{T}} = \frac{1}{75}+\frac{1}{75}+\frac{1}{75}+\frac{1}{75}$

Add up the numerator and copy the denominator:

$\frac{1}{R_{T}} = \frac{4}{75}$

Then get the reciprocal to get the total resistance:

$R _{T} = \frac{75}{4} = 18.75$

The answer to your question then is A. 18.8.

5 0

3 years ago

Read 2 more answers

Which two statements are true about the wave shown?

Andreyy89

Answer:

B and C

Explanation:

7 0

2 years ago

Read 2 more answers

What are successfulness of the Competition policy in South Africa?

Mars2501 [29]

Answer:

The product choices along with its competitive prices were provided to the consumers. Practices such as horizontal collusion and resale price maintenance was declared unlawful in 1984. Prevention of monopoly growth was the aim of the competition policy act.

Explanation:

hope this helps you

6 0

3 years ago

When you see an object that is not a light source, you are seeing light waves ___ by the object