An astronaut has a weight of 2000 kg elephant

The engine in an imaginary sports car can provide constant power to the wheels over a range of speeds from 0 to 70 miles per hou

kirill115 [55]

Answer:

Part A

it would take 6 sec

it would take 3 sec

Explanation:

We are told that the power supplied to the wheel is constant which means that the sport car is gaining energy i.e

$power \ \alpha \ energy$

Hence if power is constantly supplied energy constantly increase

From the formula of the Kinetic energy

$KE = \frac{1}{2} mv^2$

we can see that as the speed doubles from 29 mph to 58 mph the energy needed is $2^2$ = 4 times of the energy from the formula

Also the time needed would also be 4 times because energy i directly proportional to time

Hence to reach 58mph the time that it would take is

= $4* 1.5sec = 6sec$

We are told that the ground pushes the car with a constant force and

F = ma

this means that the acceleration is also constant

now from newtons law

v = u +at

Looking at it we see that final velocity is directly proportional with time

hence it would take twice the time to reach twice the final velocity

Time to reach 58mph = 3 s

since time to reach 29 mph( $\frac{1}{2} \ of \ [58mph]$ ) =( $\frac{1}{2} \ of \ 3sec$ )1.5 s

6 0

3 years ago

A 190 lb man riding a 30 lb bicycle rides up a hill 60 ft high in one minute. What is the horsepower developed during this time?

Semmy [17]

The answer is c

Explanation:

4 0

3 years ago

Oran uses a ball, a bar magnet, and a compass to create a model of Earth’s magnetic field. How could he best use these materials

bonufazy [111]

The correct answer is D, h<span>e could place the bar magnet in the ball so that the south pole of the magnet is at the top of the ball and the compass needle points to it. I hope that this helps! Have a wonderful day</span>

3 0

3 years ago

Read 2 more answers

The atomic number of an element is 19. Which is true of this element?

bezimeni [28]

C.
<span>Each atom has 19 proton
</span> the atomic number is the same as protons

4 0

3 years ago

Electrons and protons travel from the Sun to the Earth at a typical velocity of 3.83 ✕ 105 m/s in the positive x-direction. Thou

Leona [35]

Answer:

$F=2.84*10^{-26}N$ & -y direction

$F=2.84*10^{-26}N$ & +y direction

Explanation:

From the question we are told that:

Speed of electron $V_e=3.83 * 10^5 m/s$ +x direction

Earths magnetic field $B_e=3.04 * 10^-^8$ +z direction

a)

Generally the equation for magnetic force $F_m$ is mathematically given by

$F=q(V_e*B_e)$

where

$q=1.6*10^{-19}c\\\=i*\=z=-\=j$

$F=1.6*10^{-19}(3.83 * 10^5 m/s*3.04 * 10^-^8)$

$F=-2.84*10^{-26}N \=j$

Magnitude & Direction

$F=2.84*10^{-26}N$ -y direction

b)

Generally the equation for magnitude and direction of the magnetic force on an electron. is mathematically given by

$\=F'=-1.6*10^{-19}(3.83 * 10^5 m/s*3.04 * 10^-^8)$

$\=F'=-2.84*10^{-26}N \=j$

Magnitude & Direction

$F=2.84*10^{-26}N$ & +y direction

5 0

3 years ago