Which scientist and atomic model are correctly matched

(a) How can a driver steer a car traveling at constant speed so that the acceleration is zero? (Assume that the road is level. S

PilotLPTM [1.2K]

Explanation:

(a) We know that the acceleration of the car is given by :

a = change in speed / time taken

If the speed of the car is constant in a straight line, the acceleration of the car is zero because there is no change in the speed of the car.

(b) For the driver steer a car traveling at constant speed so that the magnitude of the acceleration remains constant, the driver should drive the car in the circular path. This is because, in circular path the speed of an object remains the same while its velocity changes.

8 0

3 years ago

A coffee-cup calorimeter is used to determine the heat of reaction for the reaction of compound A with compound B. A(aq) + B(aq)

Sergeeva-Olga [200]

Answer:

$\rm 1.64\times 10^{3}\; J$ .

Explanation:

Assume that his calorimeter is sufficiently effective, such that no heat had escaped to the surroundings. Heat from this solution would be absorbed by either

the solution, or
the coffee cup.

Temperature change: $33.637 - 23.722 = \rm 9.915\; ^\circ C$ .

<h3>Heat absorbed by the solution:</h3>

Only the specific heat capacity (per unit mass) of the solution is given. Both the mass of the solution and the temperature change will be required for determining the energy change. Start by finding the mass of the solution.

$m = \rho \cdot V = 2\times 16.10 \times 1.00 = \rm 32.10\; g$ .

Calculate the amount of heat absorbed from the specific heat:

$Q = c\cdot m \cdot \Delta T = 4.814\times 32.10 \times 9.915 = \rm 1335.80\; J$ .

<h3>Heat absorbed by the coffee cup:</h3>

The heat capacity of the coffee cup is given. Only the temperature change will be required for finding the amount of heat absorbed.

$Q = C\cdot \Delta T = \rm 30.7\times 9.915 = 304.391\; J$ .

<h3>Heat that this reaction produces</h3>

Find the sum of the two parts of heat. Round to three significant figures as in the heat capacity of the coffee cup and the density of the solution.

$\rm 1335.80+ 304.391 = 1.64\times 10^{3}\; J$ .

8 0

4 years ago

After a tiring first half of a basketball game, what should the players eat to get instant energy?

ANTONII [103]

A fructose-rich drink

8 0

4 years ago

Read 2 more answers

Hy would you expect sodium (Na) to react strongly with chlorine (Cl)?

erastova [34]

Chlorine needs to gain one electron and sodium needs to lose one electron

8 0

3 years ago

Two friends, Joe and Sam, go to the gym together to strength train. They decide to start off with an exercise called flat bench

astra-53 [7]

Answer:

216.31 (the work done by gravity is -216.31) positive for going up.

Explanation:

We look at this question first by getting the right equation for <em>work</em>.

Which should be... W = F x D.

From this, we can do everything, we need the Force (F) first - the question tells us that Joe is lying on his back and moves his arms upward to raise the barbell. This means that he is countering the force of graving on the object.

What is the formula for the force of gravity on an object near the earth?

Right here --- $F_{grav}$ = mg

m = the mass and...

g = the acceleration due to gravity which is <em>9.81 m/s2</em>

Before we plug things in though, we need to convert everything to SI units,

the weight is in kg - so we're good to go there, but the length of Joe's arms are in "cm" we need m or meters. Converting 70 cm to m = .7 m.

Now, we just put it all together - (31.5kg)(9.81m/s2)(.7m) = 216.31 J or 216.31 N m.

3 0

3 years ago