All categories

3 years ago

I'm working from a study guide and I got a question asking:

Physics

2 answers:

Harlamova29_29 [7]3 years ago

8 0

you need to use hours to make it easy to convert to m/s. Change 15 minutes to hours

Note distance is in km so change the time to hours to get km/hour

1 hour = 60mins so 15 minutes will be 0.25 hours

10/0.25 = 40 km/ hour

To change that to m/second, change km to meters and hour to second

it will be (40x1000) meters /3600seconds

11.1111 m/s

kakasveta [241]3 years ago

6 0

1). You're always free to use whatever units you like at the moment. Just be sure to include the units in your answer.

BUT ... If the question TELLS you what the units of your answer should be, then that's the units your answer must have.

That's what you've got here. The question said "calculate the average speed in Km h-1." That's just a fancy way to write ' km/hour '. So there's the units of your answer. The data given is in minutes, so you'll need to do some work to get the answer in km/hour .

The equation for speed is

Speed = (distance covered) / (time to cover the distance"

When you plug a number into that equation, keep the units hooked to it, and keep the units all the way through your work.

Speed = (10 km) / (15 minutes)

Speed = (10/15) (km/minutes)

Speed = 2/3 km/min

There's the speed. But the units are not what the question wants to see. You could convert the units into miles per hour, feet per second, smoots per day, furlongs per fortnight, or nano-inches per eon. But you're smart enough to know that you won't get any credit for the answer if it doesn't have the units that the question commanded you to use. So you have to convert the 'km/min' into 'km/hour'.

Just multiply your answer by (60min / hour) . That fraction is equal to ' 1 ', because the numerator and denominator are equal, so it won't CHANGE your answer by mutiplying. But you WILL convert the units of the answer.

Speed = (2/3 km/min) x (60 min/hour)

Speed = (2/3 x 60) x (km/min x min/hr)

Speed = (2/3 x 60) x (km/hr)

Speed = 40 km/hr .

You might be interested in

The strength of an electromagnet CANNOT be increased by?

zmey [24]

Answer:

reversing the current

Explanation:

4 0

3 years ago

Air will break down (lose its insulating quality) and sparking will result if the field strength is increased to about 3 × 106 N

MrRissso [65]

Answer:

Acceleration, $a=5.27\times 10^{17}\ m/s^2$

Explanation:

Given that,

Electric field strength, $E=3\times 10^6\ N/C$

Mass of the electron, $m=9.109\times 10^{-31}\ kg$

Charge on electron, $q=1.602\times 10^{-19}\ C$

Let a is the acceleration experienced by an electron. It can be calculated as :

$ma=qE$

$a=\dfrac{qE}{m}$

$a=\dfrac{1.602\times 10^{-19}\times 3\times 10^6}{9.109\times 10^{-31}}$

$a=5.27\times 10^{17}\ m/s^2$

Hence, this is the required solution.

4 0

3 years ago

Barium chlorate (ba(clo3)2) breaks down to form barium chloride and oxygen. what is the balanced equation for this reaction? whe

Margarita [4]

I think the correct answer should be Ba(ClO3)2 = BaCl2 + 3O2. In balancing chemical reactions, it important that the number of atoms of each element in each side of the reaction should be the same. Hope this answers the question. Have a nice day.

5 0

4 years ago

Read 2 more answers

A daredevil is shot out of a cannon at 31.4 ◦ to the horizontal with an initial speed of 25.9 m/s. A net is positioned a horizon

Tanzania [10]

Answer:

The net should be placed at a height of 8.45 m

Explanation:

In order to calculate the height you have to apply the equations of projectil motion.

For x-axis, the position at a time t is given by:

Xf=Xo +(VoCosα)t (I)

Where Xf is the final position, Xo is the initial position, Vo is the initial speed and t is the time.

For the y-axis, the position at a time t is given by:

Yf=Yo + (VoSinα)t - 0.5g $t^{2}$ (II)

Where Yf is the final position, Yo is the initial position, Vo is the initial speed, t is the time and g is the acceleration of gravity.

For both equations, ∝ is the angle formed by the cannon and the horizontal

The height where the net should be placed in order to catch the daredevil is given by replacing the time when the daredevil will be in the horizontal position of 39.7 m in the equation of position for the y-axis.

So, you have to calculate the time using (I)

Let the system of reference be placed at x=o and y=o

Xf= 0 + 25.9Cos(31,4◦)t

Xf=39.7

39.7=22.1t

Dividing both sides by 22.1 to find the value of t:

t=1.79 seconds

Replacing the time in equation (II) to find the height:

Yf=0 +25.9Sin(31,4◦)(1.79) - 0.5(9.8) $1.79^{2}$

Yf= 8.45 m

So the height is 8.45 m

4 0

3 years ago

Suitably qualified individuals who write prescriptions for controlled substances are assigned a number which contains two letter

daser333 [38]

B. Prescriber’s license code

8 0

4 years ago