A DC voltmeter may be used directly to measure a) frequency b)polarity c) power factor d) power

A golfer imparts a speed of 30.3 m/s to a ball, and it travels the maximum possible distance before landing on the green. the te

sergey [27]

Answer:

a) Time spend by ball in air = 4.368 seconds

b) Longest hole that golfer can make = 93.59 meter

Explanation:

Projectile motion has two types of motion Horizontal and Vertical motion.

Vertical motion:

We have equation of motion, v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration and t is the time taken.

Considering upward vertical motion of projectile.

In this case, Initial velocity = vertical component of velocity = u sin θ, acceleration = acceleration due to gravity = -g $m/s^2$ and final velocity = 0 m/s.

0 = u sin θ - gt

t = u sin θ/g

Total time for vertical motion is two times time taken for upward vertical motion of projectile.

So total travel time of projectile = 2u sin θ/g

Horizontal motion:

We have equation of motion , $s= ut+\frac{1}{2} at^2$ , s is the displacement, u is the initial velocity, a is the acceleration and t is the time.

In this case Initial velocity = horizontal component of velocity = u cos θ, acceleration = 0 $m/s^2$ and time taken = 2u sin θ /g

So range of projectile, $R=ucos\theta*\frac{2u sin\theta}{g} = \frac{u^2sin2\theta}{g}$

a) We have golf ball travels maximum distance, so range is maximum.

Maximum range is when, sin 2θ =1

=> θ = 45⁰

Now we have travel time of projectile, t = 2u sin θ/g

Initial velocity = 30.3 m/s and θ = 45⁰

So time spend in air, t = $\frac{2*30.3*sin45}{9.81} =4.368 seconds$

b) Longest hole that golfer can make = Range of projectile = $\frac{u^2sin2\theta}{g}$

Longest hole that golfer can make = $\frac{30.3^2sin(2*45)}{9.81}=93.59 meter$

4 0

2 years ago

The liquid pressure varies with depth why

Solnce55 [7]

Explanation:

Hey, there!

The liquid pressure varies with depth because liquid pressure is directly proportional to the depth of liquid from the free surface of the liquid. so, more the depth more the pressure and less the depth less the pressure.

Hope it helps...

3 0

3 years ago

You want to build a search light. The search light is to have an outgoing parallel beam. You have a small, very bright light (a

andrew11 [14]

Answer:

1 m

Explanation:

Given

The mirror is a concave mirror.

Radius of curvature = 2 m

Now, for a parallel beam after reflection occurs, the object should be placed at the focus of the mirror.

We know, focal length = radius of curvature / 2

= 2 / 2

= 1

Thus the focal length is 1 m.

Hence the object should be placed at 1 m from the concave mirror for parallel beam reflection.

3 0

3 years ago

What can we say about energy on

Marina CMI [18]

Answer:

A. Longer wavelengths and less dangers

Explanation:

Radio waves are at the lowest end of the EM spectrum, they have the longest wavelength of any other EM waves, the lowest energy and, accordingly, the lowest frequency;

Their low energy and frequency means they pose little risk of harm or danger as they don't get absorbed by human being.

8 0

2 years ago

What is the weight of an object (mass = 60 kilograms) on Mars, where the acceleration due to gravity is 3.75 meters/second2?. Se

aev [14]

We know that:
w=mg
w=60kg*3,75m/s²
w=225N (d)

3 0

2 years ago

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