What is the wavelength of an earthquake wave if it has a speed of 7 km/s and a frequency of 3 Hz?

A water-balloon launcher with mass 5 kg fires a 1 kg balloon with a velocity of

Mashcka [7]

1.6 m/s west is the answer

3 0

3 years ago

In Example 2.12, two circus performers rehearse a trick in which a ball and a dart collide. Horatio stands on a platform 6.4 m a

pickupchik [31]

Answer:

time of collision is

t = 0.395 s

$h = 5.63 m$

so they will collide at height of 5.63 m from ground

Explanation:

initial speed of the ball when it is dropped down is

$v_1 = 0$

similarly initial speed of the object which is projected by spring is given as

$v_2 = 16.2 m/s$

now relative velocity of object with respect to ball

$v_r = 16.2 m/s$

now since we know that both are moving under gravity so their relative acceleration is ZERO and the relative distance between them is 6.4 m

$d = v_r t$

$6.4 = 16.2 t$

$t = 0.395 m$

Now the height attained by the object in the same time is given as

$h = v_2 t - \frac{1}{2}gt^2$

$h = 16.2(0.395) - \frac{1}{2}(9.81).395^2$

$h = 5.63 m$

so they will collide at height of 5.63 m from ground

4 0

3 years ago

Un pintor de 75.0 kg sube por una escalera de 2.75 m que está inclinada contra una pared vertical. La escalera forma un ángulo d

dezoksy [38]

Answer:

Work done, W = 1786.17J

Explanation:

The question says "A 75.0-kg painter climbs a 2.75-m ladder that is leaning against a vertical wall. The ladder makes an angle of 30.0 ° with the wall. How much work (in Joules) does gravity do on the painter? "

Mass of a painter, m = 75 kg

He climbs 2.75-m ladder that is leaning against a vertical wall.

The ladder makes an angle of 30 degrees with the wall.

We need to find the work done by the gravity on the painter.

The angle between the weight of the painter and the displacement is :

θ = 180 - 30

= 150°

The work done by the gravity is given by :

$W=Fd\cos\theta\\\\=75\times 10\times 2.75\times \cos30\\\\=1786.17\ J$

Hence, the required work done is 1786.17 J.

6 0

2 years ago

_____ is the transfer of thermal energy between two bodies which are at different temperatures. The si unit for this is the joul

ss7ja [257]

Answer:

Heat

Explanation:

The thermal energy is usually defined as a heat energy that occurs due to the increase in temperature. Due to this increasing temperature, the atoms, as well as the molecules, start to migrate at a much faster rate and rapid collisions occur with one another.

This temperature change that is involved in this process can be measured.

Thus, in thermal energy, heat (heat energy) is transferred from one body to another at different distinct temperatures.

The SI unit of heat is Joule.

6 0

3 years ago

You need to design a photodetector that can respond to the entire range of visible light. True or False

Rasek [7]

Answer: True

Explanation:

A photo detector that can respond to the entire rang of visible light can be design, it is true.

Photo detector is a device in an optical receiver which receives optical signals and convert it to electric signal. It is the key device position in front of the optical receiver.

7 0

3 years ago