Will give brainliest! how does an engineer use physical science?

5. A man in a car is listening to the radio. The radio station is broadcasting at a frequency of 85 MHz from two radio transmitt

nasty-shy [4]

Answer:

Speed = 0.00392 m/s

Explanation:

Solution:

Frequency of the radio = 85 MHz

If we have the frequency, we can calculate the wavelength of the radio wave.

As we know,

Frequency = speed of light/wavelength

wavelength = c/f

c = speed of light = 3 x $10^{8}$ m/s

So,

Wavelength = 3 x $10^{8}$ m/s / 85 x $10^{6}$ Hz

Wavelength = 3.5294 m

Man gets disturbed reception at t = 15 min

t = 15 x 60 = 900 s

t = 900 s

Speed = distance/time

Here, distance is wavelength. So,

Speed = 3.5294 m / 900 s

Speed = 0.00392 m/s

Hence, the man's car is going with speed of 0.00392 m/s

3 0

3 years ago

A baseball player exerts a force of 100 N on a ball for a distance of 0.5 mas he throws it. If the ball has a mass of 0.15 kg, w

Aloiza [94]

Answer:

25.82 m/s

Explanation:

We are given;

Force exerted by baseball player; F = 100 N

Distance covered by ball; d = 0.5 m

Mass of ball; m = 0.15 kg

Now, to get the velocity at which the ball leaves his hand, we will equate the work done to the kinetic energy.

We should note that work done is a measure of the energy exerted by the baseball player.

Thus;

F × d = ½mv²

100 × 0.5 = ½ × 0.15 × v²

v² = (2 × 100 × 0.5)/0.15

v² = 666.67

v = √666.67

v = 25.82 m/s

4 0

3 years ago

To get a feeling for inertial forces discuss the familiar cases of accelerating in a car in a straight line while increasing or

inn [45]

Answer:

Explanation:

When we accelerate in a car on a straight path we tend to lean backward because our lower body part which is directly in contact with the seat of the car gets accelerated along with it but the upper the upper body experiences this force later on due to its own inertia. This force is accordance with Newton's second law of motion and is proportional to the rate of change of momentum of the upper body part.

Conversely we lean forward while the speed decreases and the same phenomenon happens in the opposite direction.

While changing direction in car the upper body remains in its position due to inertia but the lower body being firmly in contact with the car gets along in the direction of the car, seems that it makes the upper body lean in the opposite direction of the turn.

On abrupt change in the state of motion the force experienced is also intense in accordance with the Newton's second law of motion.

7 0

3 years ago

A 65 Kg roller-blade is accelerating at 5 m/s/s across the side walk. What force would be necessary for this acceleration to occ

Neporo4naja [7]

Newton's second law states that the force applied to an object is equal to the product between the mass m of the object and its acceleration a:
$F=ma$
Using $m=65 kg$ and $a=5 m/s^2$ , we can find the value of the force applied to the roller-blade to obtain this acceleration:
$F=(65 kg)(5 m/s^2)=325 N$