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3 years ago

What two measurements are needed to determine density?

2 answers:

7 0

Density is defined as (mass) per unit (volume). So in order to calculate
the density of a glob of some substance, you pretty much have to measure
its mass and its volume.

svp [43]3 years ago

4 0

mass & volume

$Density = \frac{mass}{volume}$

You might be interested in

Rest and motion are relative terms. write in brief

Greeley [361]

Answer:

Rest and motion are the relative terms because they depend on the observer's frame of reference. So if two different observers are not at rest with respect to each other, then they too get different results when they observe the motion or rest of a body.

Explanation With Example:

Imagine you are sitting inside a moving bus. When you look outside you will observe that you are moving. ... With respect to the roof of bus, you are at rest. Hence it is concluded that rest and motion are relative terms.

5 0

3 years ago

Calculate the broadcast wavelength of the radio station 99.90 fm. seconds

taurus [48]

The radio waves are electromagnetic wave, so it travels with velocity of light i.e $3\times 10^{8} \ m/s$ .

We can use the relation between frequency, wavelength and speed as

$\lambda =\frac{c}{f}$

Here c is speed of light, $\lambda$ is wavelength and f is frequency and its value is given 99.90 FM, it is actually in megahertz (i.e 99.90 MHz).

Therefore,

$\lambda =\frac{3 \times 10^{8}\ m/s }{99.90 \times 10^{6} \ Hz} = 3.003 \ m$ .

Thus, the broadcast wavelength of the given radio station is 3.003 m.

8 0

3 years ago

A hiker walks 20.51 m at 33.16 degrees. What is the Y component of his displacement?

Serhud [2]

Answer:

The y component of his displacement is 11.22 meters

Explanation:

Components of the displacement

The displacement is a vector because it has a magnitude and a direction. Let's suppose a displacement has a magnitude r and a direction θ, measured with respect to the positive x-direction. The horizontal component of the displacement is calculated by:

$x=r\cos\theta$

The vertical component is calculated by:

$y=r\sin\theta$

The hiker has a displacement with magnitude r = 20.51 m at an angle of 33.16 degrees. Substituting in the above equation:

$y=20.51\sin(33.16^\circ)$

$y=11.22\ m$

The y component of his displacement is 11.22 meters

7 0

3 years ago

An Olympic track runner starts from rest and has an acceleration of 2.4 m/s2 for 3.6 s, then has zero acceleration for the remai

rjkz [21]

Answer:

The runner's speed at the following times would remain 8.64 m/s.

Explanation:

Acceleration definition: Acceleration is rate of change in velocity of an object with respect to time.

In this case, after 3.6 seconds the acceleration is zero, it means that the velocity of the runner after 3.6 seconds is not changing and it will remain constant for the remainder of the race. Now, we have to find the velocity of the runner that he had after 3.6 seconds and that would be the runner's speed for the remainder of the race. For this we use first equation of motion.

First equation of motion: Vf = Vi + a×t

Vf stands for final velocity

Vi stands for initial velocity

a stands for acceleration

t stands for time

In the question, it is mentioned that the runner starts from rest so its initial velocity (Vi) will be 0 m/s.

The acceleration (a) is given as 2.4 m/s²

The time (t) is given as 3.6 s

Now put the values of Vi, a and t in first equation of motion

Vf = Vi + a×t

Vf = 0 + 2.4×3.6

Vf = 2.4×3.6

Vf = 8.64 m/s

So,the runner's speed at the following times would remain 8.64 m/s.

5 0

3 years ago

A small rubber ball is thrown at a heavier, larger basketball that is still. The small ball bounces off the basketball. Assume t

svp [43]

The forces are the same for part A

6 0

3 years ago

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