1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
UNO [17]
3 years ago
13

A rifle that shoots bullets at 477 m/s is to be aimed at a target 45.5 m away. If the center of the target is level with the rif

le, how high above the target must the rifle barrel be pointed so that the bullet hits dead center?

Physics
1 answer:
Free_Kalibri [48]3 years ago
5 0

Answer:

The rifle barrel must be pointed at a height of 4.45cm above the target so that the bullet hits dead center.

Explanation:

First, we need to sketch the situation so we can have a better idea of what the problem looks like (Refer to uploaded picture).

So as you may see in the drawing, when pointing the rifle to the target, we can see it as a triangle, but in reality, the bullet will have a parabolic trajectory. Both points of view will help us determine what the height must be. In order to find it, we need to first determine at what angle the bullet should be shot. In order to do so we can use the range formula, which looks like this:

R=\frac{v^{2}sin(2\theta)}{g}

Where R is the range of the bullet (this is how far it goes before it has the

same height it was shot from), v is the original speed of the bullet, θ is the angle at which the bullet is shot and g is the acceleration of gravity.

We can solve this equation for theta, so we get:

gR=v^{2}sin(2\theta)

\frac{gR}{v^{2}}=sin(2\theta)

sin^{-1}(\frac{gR}{v^{2}})=2\theta

\theta=\frac{sin^{-1}(\frac{gR}{v^{2}})}{2}

so now we can substitute the given data:

\theta=\frac{sin^{-1}(\frac{(9.8m/s^{2})(45.5m)}{(477m/s)^{2}})}{2}

so we get:

θ=0.05614°

once we get the angle, we can look at the triangle diagram. From the drawing we can see that we can use the tan function to find the height:

tan \theta = \frac{h}{45.5m}

so we can solve this for h, so we get:

h=45.5m*tan(0.05614^{o})

which yields:

h=0.0445m

or

h=4.45cm

You might be interested in
An electron is released form rest in a region of space where a uniform electric field is present. Joanna claims that its kinetic
djyliett [7]

Answer:

Neither.

Explanation:

When an electron is released from rest, in an uniform electric field, it will accelerate moving in a direction opposite to the field (as the field has the direction that it would take a positive test charge, and the electron carries a negative charge).

It will move towards a point  with a higher potential, so its kinetic energy will increase, while its potential energy will decrease:

⇒ ΔK + ΔU = 0 ⇒ ΔK = -ΔU = - (-e*ΔV)

As ΔV>0, we conclude that the electric potential energy decreases while the kinetic energy increases in the same proportion, in order to energy be conserved, in absence of non-conservative forces.

4 0
3 years ago
Can someone help me with this please?​
Nikolay [14]

Answer:

Explanation:

umm... try 30

4 0
3 years ago
A block is being pulled upward along an inclined surface at a constant speed. Which of the following statements is correct? Grou
Alex17521 [72]

Answer:The net force on the block is zero.

Explanation:

Given

Block is being pulled upward along an inclined surface at a constant speed

As speed is constant and moved in a straight line along the plane therefore its velocity is also constant .

and change in velocity is equal to acceleration therefore acceleration is zero here i.e. net force is zero acting on the body.

5 0
3 years ago
Sunshine Corporation is expected to pay a dividend of $1.50 in the upcoming year. Dividends are expected to grow at the rate of
grigory [225]

Answer:

$25

Explanation:

The computation of the intrinsic value of the stock is shown below:

As we know that

Intrinsic value or Price = Dividend ÷ (Cost of equity - growth rate)

where,

Cost of equity or ke  is

= Risk free rate of return  + beta × (Market rate of return - risk free rate of return)

= 6% + 0.75 × (14% - 6%)

= 12 %

So the intrinsic value is

= $1.50 ÷ (12% - 6%)

= $25

7 0
3 years ago
Read 2 more answers
Read this quotation:
Brums [2.3K]

Answer:

the Princess in "St. George and the Dragon"

4 0
3 years ago
Read 2 more answers
Other questions:
  • Which of the following is true concerning atoms?Atoms are made of even smaller substances called subatomic particles
    15·1 answer
  • a Ferrari with an initial velocity of 10 m/s, comes to a complete stop in 5 seconds, what will its acceleration be?
    12·2 answers
  • What is 52,427 equal in scientific notation
    14·2 answers
  • A scientist prepares a colloidal solution and pours it into a glass tank. She then flashes a beam of white light into one end of
    7·2 answers
  • A 12 A fuse is placed in a parallel circuit that has two branches. 8 A flows in branch 1 and 6 A flows in branch 2. This fuse
    15·1 answer
  • An old iron battery was discarded in this meadow. The iron in the battery is undergoing a ____ change as it rusts. The rusting i
    13·2 answers
  • An electron travels west to east with a kinetic energy of 10 keV. The Earth's magnetic field in Pittsburgh is 19,911.5 nT in the
    9·1 answer
  • Can anyone help me please​
    7·1 answer
  • The acceleration due to gravity on the moon is about 5.4ft/s2. if your weight is 150lbf on earth
    10·1 answer
  • Hello, are there any furries, artists, equestrians, gamers, athletes, etc? If so reply down below
    12·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!