Which one requires more work walking 1 mile running 1 mile

RSB [31]

Answer:

c)both

Explanation:

The laws of reflection hold true for all the reflecting surfaces either spherical or plane. Therefore, the plane mirror, concave mirror and the convex mirror all will follow the laws of reflection.

5 0

3 years ago

Read 2 more answers

How do we write 0.00846 as a scientific notation?<br>

Nadusha1986 [10]

Answer:

Explanation:

m × 10n, where m is a number between 1 and 10 ( 1 ≤ |m| < 10 ) and the exponent n is a positive or negative integer.

3 0

3 years ago

Rodney is trying out one of Santa's new games that consists of three pieces that blow apart if the wrong key is inserted into th

ch4aika [34]

Answer:

<em>The third piece moves at 6.36 m/s at an angle of 65° below the horizon</em>

Explanation:

Linear Momentum

It's a physical magnitude that measures the product of the velocity by the mass of a moving object. In a system where no external forces are acting, the total momentum remains unchanged regardless of the interactions between the objects in the system.

If the velocity of an object of mass m is $\vec v$ , the linear momentum is computed by

$\displaystyle \vec{P}=m.\vec{v}$

a)

The momentum of the board before the explosion is

$\displaystyle \vec{P}_{t1}=m_t\ \vec{v}_o$

Since the board was initially at rest

$\displaystyle \vec{P}_{t1}=$

After the explosion, 3 pieces are propelled in different directions and velocities, and the total momentum is

$\displaystyle \vec{P}_{t2}=m_1\ \vec{v}_1\ +\ m_2\ \vec{v}_2+m_3\ \vec{v}_3$

The first piece of 2 kg moves at 10 m/s in a 60° direction

$\displaystyle \vec{v}_1=(10\ m/s,60^o)$

We find the components of that velocity

$\displaystyle \vec{v}_1=$

$\displaystyle \vec{v}_1=m/s$

The second piece of 1.2 kg goes at 15 m/s in a 180° direction

$\displaystyle \vec{v}_2=(15,180^o)$

Its components are computed

$\displaystyle \vec{v}_2=(15\ cos180^o,15\ sin180^o)$

$\displaystyle \vec{v}_2=(-15,0)\ m/s$

The total momentum becomes

$\displaystyle P_{t2}=2+1.2+m_3\ \vec{v}_3$

Operating

$\displaystyle P_{t2}=++m_3\ \vec{v}_3$

Knowing the total momentum equals the initial momentum

$\displaystyle P_{t2}=+m_3\ \vec{v}_3=0$

Rearranging

$\displaystyle m_3\ \vec{v}_3=$

Calculating

$\displaystyle m_3\ \vec{v}_3=$

This is the momentum of the third piece

b)

From the above equation, we solve for $\vec v_3$ :

$\displaystyle \vec{v}_3=\frac{1}{3}$

$\displaystyle \vec{v}_3=m/s$

The magnitude of the velocity is

$\displaystyle \vec{v}_3|=\sqrt{2.67^2+(-5.77)^2}=6.36$

And the angle is

$\displaystyle tan\theta =\frac{-5.77}{2.67}=-2.161$

$\displaystyle \theta =-65.17^o$

The third piece moves at 6.36 m/s at an angle of 65° below the horizon

5 0

4 years ago

2. A 1750 kg car accelerates at a rate of 4.0 m/s2. How much force is the cars engine producing?

8090 [49]

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 1750 × 4

We have the final answer as

Hope this helps you

6 0

3 years ago

What is the volume of 220 grams of an object with a density of 55/cm3

Naddika [18.5K]

Every cm³ of that substance has 55 grams of mass
packed into it. That's what density means.

So how many cm³ do you need in order to stuff in
220 grams ?

How many 55s make 220 ?

220/55 = 4 .

If you have 4 cm³ of space available, you can pack
the whole 220 grams into that volume, because each cm³
will hold 55 grams, and 4 x 55 = 220 .

5 0

4 years ago