An earthquake causes a 3 kg book to fall from a shelf. If the book lands with

Q7) A box sliding with a velocity of 5 m/s accelerates at 2 m/s^2. How

grigory [225]

Answer:

The box displacement after 6 seconds is 66 meters.

Explanation:

Let suppose that velocity given in statement represents the initial velocity of the box and, likewise, the box accelerates at constant rate. Then, the displacement of the object ( $\Delta s$ ), in meters, can be determined by the following expression:

$\Delta s = v_{o}\cdot t+\frac{1}{2}\cdot a\cdot t^{2}$ (1)

Where:

$v_{o}$ - Initial velocity, in meters per second.

$t$ - Time, in seconds.

$a$ - Acceleration, in meters per square second.

If we know that $v_{o} = 5\,\frac{m}{s}$ , $t = 6\,s$ and $a = 2\,\frac{m}{s^{2}}$ , then the box displacement after 6 seconds is:

$\Delta s = 66\,m$

The box displacement after 6 seconds is 66 meters.

5 0

2 years ago

Two students are on a balcony 19.1 m above the street. One student throws a ball, b1, vertically downward at 13.9 m/s. At the sa

tester [92]

Answer:

Part a)

$t = 2.83 s$

Part b)

Ball thrown downwards = $v_f = 23.8 m/s$

Ball thrown upwards = $v_f = 23.8 m/s$

Part c)

$d = 22.24 m$

Explanation:

Part a)

Since both the balls are projected with same speed in opposite directions

So here the time difference is the time for which the ball projected upward will move up and come back at the same point of projection

Afterwards the motion will be same as the first ball which is projected downwards

so here the time difference is given as

$\Delta y = 0 = v_y t + \frac{1}{2}at^2$

$0 = 13.9 t - \frac{1}{2}(9.81) t^2$

$t = 2.83 s$

Part b)

Since the displacement in y direction for two balls is same as well as the the initial speed is also same so final speed is also same for both the balls

so it is given as

$v_f^2 - v_i^2 = 2 a \Delta y$

$v_f^2 - (13.9)^2 = (2)(-9.81)(-19.1)$

$v_f^2 = 567.9$

$v_f = 23.8 m/s$

Part c)

Relative speed of two balls is given as

$v_{12} = v_1 - v_2$

$v_{12} = (13.9) - (-13.9) = 27.8 m/s$

now the distance between two balls in 0.8 s is given as

$d = v_{12} t$

$d = 27.8 \times 0.8$

$d = 22.24 m$

7 0

3 years ago

Billy drops a water balloon from the roof of his house. Since the balloon began with an original velocity of zero how far above

VashaNatasha [74]

T=2,5s
a=g≈10m/s²

h=s=?

$s= \frac{1}{2} at^2 \Leftrightarrow h=\frac{1}{2}gt^2=\frac{1}{2}*10m/s^2 *(2,5s)^2=5m/s^2* \frac{25}{4} s^2=\boxed{31,25m}$

"Non nobis, Domine, non nobis, sed Nomini tuo da gloriam."

Regards M.Y.

7 0

3 years ago

What's the difference and similarity between O2 and 2 O ?

nasty-shy [4]

O2 refers to two oxygen atoms bonded together, while 2 O refers to two oxygen atoms that are not bonded to each other. They both have two oxygen atoms, but in O2, the oxygen atoms are bonded, while in 2O, the atoms are not.

4 0

2 years ago

When a chemical reaction occurs,

mel-nik [20]

A) reactants interact to form products with different chemical and physical properties

3 0

2 years ago