Given :
A 13.3 kg box sliding across the ground decelerates at 2.42 m/s².
To Find :
The coefficient of kinetic friction.
Solution :
Frictional force applied to the box is :
....1)
Also, force of friction is given by :
....2)
Equating equation 1) and 2), we get :

Therefore, the coefficient of kinetic friction is 0.247 .
Answer:
Victor will always be able to select 4 of those cards with the following property
Explanation:
Number of trading cards = 100
victor selects 21 cards
let the 4 cards be labelled : A,B,C and D
The average power level of : A,B,C,D = ( A + B + C + D )/ 4 = P
let the two pairs be : ( A + B ) and ( C + D )
note: average power of each pair = P and this shows that
( A + B ) = ( C + D ) for Victor to select 4 cards out of the 21 cards that exhibit the same property
we have to check out the possible choices of two cards out of 21 cards yield distinct sums.
= C(21,2)=(21x20)/2 = 210.
from the question the number of distinct sums that can be created using 101 through 200 is < 210 .
hence it is impossible to get 210 distinct sums therefore Victor will always be able to select 4 of those cards
Answer:
95 minutes
Explanation:
According to N.A.S.A, the Hubble Space Telescope makes one orbit around Earth every 95 minutes.
"The Hubble Space Telescope is a large telescope in space. It was launched into orbit by space shuttle Discovery on April 24, 1990. Hubble orbits about 547 kilometers (340 miles) above Earth. It is the length of a large school bus and weighs as much as two adult elephants. Hubble travels about 5 miles per second: That is like traveling from the eastern coast of the United States to the western coast in 10 minutes. Hubble is solar-powered.
Hubble takes sharp pictures of objects in the sky such as planets, stars and galaxies. Hubble has made more than one million observations. These include detailed pictures of the birth and death of stars, galaxies billions of light years away, and comet pieces crashing into Jupiter's atmosphere.
Scientists have learned a lot about the universe from these pictures. Many of them are beautiful to look at."
Answer:
Explanation:
85 = ½(0.43)t²
t = √(2(85)/0.43)
t = 19.883380...
t = 20 s
v→ 8.55 m/s initial, 0 m/s final
a← 0.43 m/s²
Answer:
<em>The glider's new speed is 68.90 m/s</em>
Explanation:
<u>Principle Of Conservation Of Mechanical Energy</u>
The mechanical energy of a system is the sum of its kinetic and potential energy. When the only potential energy considered in the system is related to the height of an object, then it's called the gravitational potential energy. The kinetic energy of an object of mass m and speed v is

The gravitational potential energy when it's at a height h from the zero reference is

The total mechanical energy is


The principle of conservation of mechanical energy states the total energy is constant while no external force is applied to the system. One example of a non-conservative system happens when friction is considered since part of the energy is lost in its thermal manifestation.
The initial conditions of the problem state that our glider is glides at 416 meters with a speed of 45.2 m/s. The initial mechanical energy is

Operating in terms of m


Then we know the glider dives to 278 meters and we need to know their final speed, let's call it
. The final mechanical energy is

Operating and factoring

Both mechanical energies must be the same, so

Simplifying by m and rearranging

Computing

The glider's new speed is 68.90 m/s