Speed is a scalar quantity (meaning it can be measured using a single number that represents the amount), while velocity is composed of the scalar quantity plus the direction. As the 100-meter sprint only takes place in one direction, the speed and velocity for this is just the same. For the 400-meter sprint however, the direction of your speed changes as you turn for her curved part of the race. Therefore, a direction change is happening.
Answer:
upwards
downwards
Explanation:
Given:
weight of the person,
So, the mass of the person:
- Now if the apparent weight in the elevator,
<u>Then the difference between the two weights is :</u>
is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:
upwards, because the normal reaction that due to the weight of the body is increased here.
- Now if the apparent weight in the elevator,
<u>Then the difference between the two weights is :</u>
is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:
downwards, because the normal reaction that due to the weight of the body is decreased here.
Answer:
Every object has a different density and therefore carries different properties. When rays of white light strike an object, each ray light strikes the object with different frequency and therefore is absorbed and reflected differently from the host object.
In case if all the frequencies are absorbed by the object, it turns out to be black in color. Whereas on the other hand, if it is a mix of absorption and reflection, it makes different colors based on its frequencies and other properties of the object.
Answer:
In order to improve visibility
Explanation:
Infrared telescopes are made using infrared cameras that contain infrared detectors which are solid-state and are maintained at very cold (cryogenic) temperatures
Infrared radiation is absorbed by water vapor which is present in the Earth's atmosphere, leading to the limitation of the use of infra red telescopes at high altitudes such as mountains, high flying planes or satellites
Answer: The bottom of the ladder is moving at 3.464ft/sec
Explanation:
The question defines a right angle triangle. Therefore using pythagorean
h^2 + l^2 = 10^2 = 100 ...eq1
dh/dt = -2ft/sec
dl/ dt = ?
Taking derivatives of time in eq 1 on both sides
2hdh/dt + 2ldl/dt = 0 ....eq2
Putting l = 5ft in eq2
h^ + 5^2 = 100
h^2 = 25 = 100
h Sqrt(75)
h = 8.66 ft
Put h = 8.66ft in eq2
2 × 8.66 × (-2) + 2 ×5 dl/dt
dl/dt = 17.32 / 5
dl/dt = 3.464ft/sec