Let x = the angle of elevation for shooting the arrow.

Assume
g = 9.8 m/s²
No wind resistance
The vertical launch velocity is 25.1 sin(x) m/s
The horizontal velocity is 25.1 cos(x) m/s

The time of flight is
24/[25.1 cos(x)] s = 0.9562 sec(x) s

Therefore
0.5*[0.9562 sec(x)]*(9.8) = 25.1 sin(x)
4.6854 = 25.1* sin(x)cos(x)
sin(2x) = 0.3733
2x = sin⁻¹ 0.3733 = 21.92 deg
x = 10.96 deg

Answer: 11 degrees (nearest integer)

8 0

4 years ago

Read 2 more answers

What do you know about muscular fitness activities?

Ulleksa [173]

Answer:

Examples of muscle-strengthening activities include:

lifting weights.

working with resistance bands.

heavy gardening, such as digging and shovelling.

climbing stairs.

hill walking.

cycling.

dance.

push-ups, sit-ups and squats.

Explanation:

3 0

3 years ago

Is it safe to drive your 1600-kg car at speed 34 m/s around a level highway curve of radius 190 m if the effective coefficient o

adoni [48]

Answer:

It is unsafe

Explanation:

v = Velocity of car = 34 m/s

r = Radius of turn = 190 m

$\mu$ = Coefficient of static friction = 0.5

m = Mass of car = 1600 kg

g = Acceleration due to gravity = 9.81 m/s²

The centripetal force is given by

$F_c=m\frac{v^2}{r}\\\Rightarrow F_c=1600\frac{34^2}{190}\\\Rightarrow F_c=9734.73\ N$

The frictional force is given by

$F_f=\mu mg\\\Rightarrow F_f=0.5\times 1600\times 9.81\\\Rightarrow F_f=7848\ N$

If the centripetal force is greater than the frictional force then the car will slip which makes it unsafe.

Here, the centripetal force is greater than the frictional force which makes it unsafe to drive it at that speed.

4 0

3 years ago

A child is swinging back and forth with a constant period and amplitude. Somewhere in front of the child, a stationary horn is e

Amanda [17]

Answer:

Explanation:

We shall apply concept of Doppler's effect of apparent frequency to this problem . Here observer is moving sometimes towards and sometimes away from the source . When observer moves towards the source , apparent frequency is more than real frequency and when the observer moves away from the source , apparent frequency is less than real frequency . The apparent frequency depends upon velocity of observer . The formula for apparent frequency when observer is going away is as follows .

f = f₀ ( V - v₀ ) / V , f is apparent , f₀ is real frequency , V is velocity of sound and v is velocity of observer .

f will be lowest when v₀ is highest .

velocity of observer is highest when he is at the equilibrium position or at middle point .

So apparent frequency is lowest when observer is at the middle point and going away from the source while swinging to and from before the source of sound .

3 0

3 years ago