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babymother [125]

3 years ago

10

Silvia is driving at the speed limit of 25m/s when she sees an ambulance approaching in her rearview mirror. To move out of its

way, she accelerates to 32 m/s in 3 seconds. What was her acceleration.

1 answer:

lesya692 [45]3 years ago

6 0

a = ∆v/t = (32 - 25) / 3 = 7/3 m/s2

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A convex mirror is placed to the right of an object. The image formed by the mirror will be a

kotegsom [21]

Answer:If you look at the image of the toy car in the mirror, it will appear to be the same ... However, there is a virtual focal point on the other side of the mirror if we follow them ... Concave mirrors, on the other hand, can have real images. ... Naturally, in concave mirror, the closer the image to the mirror, the bigger the image formed.

8 0

3 years ago

Read 2 more answers

The filament of a certain lamp has a resistance that increases linearly with temperature. When a constant voltage is switched on

alekssr [168]

Answer:

The change in temperature is $\Delta T = 1795 K$

Explanation:

From the question we are told that

The temperature coefficient is $\alpha = 4 * 10^{-3 }\ k^{-1 }$

The resistance of the filament is mathematically represented as

$R = R_o [1 + \alpha \Delta T]$

Where $R_o$ is the initial resistance

Making the change in temperature the subject of the formula

$\Delta T = \frac{1}{\alpha } [\frac{R}{R_o} - 1 ]$

Now from ohm law

$I = \frac{V}{R}$

This implies that current varies inversely with current so

$\frac{R}{R_o} = \frac{I_o}{I}$

Substituting this we have

$\Delta T = \frac{1}{\alpha } [\frac{I_o}{I} - 1 ]$

From the question we are told that

$I = \frac{I_o}{8}$

Substituting this we have

$\Delta T = \frac{1}{\alpha } [\frac{I_o}{\frac{I_o}{8} } - 1 ]$

=> $\Delta T = \frac{1}{3.9 * 10^{-3}} (8 -1 )$

$\Delta T = 1795 K$

6 0

4 years ago

A rock is thrown with a force of 500 N and an acceleration is 75 m/s^2. What is its mass?

artcher [175]

Answer:

We conclude that the mass of a rock with a force of 500 N and an acceleration of 75 m/s² is 6.7 kg.

Hence, option D is correct.

Explanation:

Given

Force F = 500 N

Acceleration a = 75 m/s²

To determine

Mass m = ?

Important Tip:

The mass of a rock can be found using the formula F = ma

Using the formula

$F = ma$

where

F is the force (N)

m is the mass (kg)

a is the acceleration (m/s²)

now substituting F = 500, and a = 75 m/s² in the formula

$F = ma$

$500 = m(75)$

switch sides

$m\left(75\right)=500$

Divide both sides by 75

$\frac{m\cdot \:75}{75}=\frac{500}{75}$

simplify

$m=\frac{20}{3}$

$m=6.7$ kg

Therefore, we conclude that the mass of a rock with a force of 500 N and an acceleration of 75 m/s² is 6.7 kg.

Hence, option D is correct.

7 0

3 years ago

You want to move a heavy box with mass 30.0 across a carpeted floor. You pull hard on one of the edges of the box at an angle 30

ivolga24 [154]

Answer:

Explanation:

Check attachment for solution

6 0

3 years ago

Jimmy is standing 300 feet away from a rocket that is being shot up into the air away from him at an angle of elevation of 70 de

ira [324]

Answer: Vertical height of rocket is 824.24ft

Explanation: see attachment.

Opp/ Adj = Tan 70°

h/ 300 = Tan 70°

h= 300tan 70°

h = 824.24ft

4 0

3 years ago