An airplane lands with an initial velocity of 60 m/s and then slows down at 1.5 m/s2 for 30 seconds. What is its final velocity?

The universal law of gravitation states that the force of attraction between two objects depends on which quantities?

Ronch [10]

Answer:

D. the masses of the objects and the distance between them

Explanation:

Gravitation is a force, a force doesn't care about the shape or density of objects, only about their masses... and distances.

And you can get it using the following equation:

$f = \frac{Gm_{1}m_{2} }{d^{2} }$

Where :

G is the universal gravitational constant : G = 6.6726 x 10-11N-m2/kg2

m represent the mass of each of the two objects

d is the distance between the centers of the objects.

4 0

3 years ago

A highly volatile substance has an initial mass of 1200 g and its mass is reduced by 12% each second.

Softa [21]

Answer:

Explanation:

a) 1.00 - 0.12 = 0.88

m = 1200(0.88)^t

b) t = ln(m/1200) / ln(0.88)

c) m = 1200(0.88)^10 = 334.20 g

d) t = ln(10/1200) / ln(0.88) = 37.451... = 37 s

e) t = ln(1/1200) / ln(0.88) = 55.463... = 55 s

4 0

3 years ago

Which of the following is NOT a type of sediment?

MatroZZZ [7]

Answer:

It's soil.

Explanation:

7 0

2 years ago

A uniform steel girder of weight 22KN and of length 12m is lifted off the ground at one end by means of a crane. When the raised

Keith_Richards [23]

Answer:

Explanation:

For free body diagram see attached sheet .

W is weight of steel girder acting at the middle point of its length . T is tension in the cable .

OB = √ ( 12² - 2² )

= 11.83 m .

OC = 11.83 / 2 = 5.915 m

Taking moment of tension T and weight W about point O

W x OC = T x OB

22 x 5.915 = T x 11.83

T = 22 x 5.915 / 11.83

= 11 kN

Considering forces acting in vertical direction and equating forces in opposite direction

T + R = W

R = W - T

= 22 - 11 = 11 KN

So force of grinder on the ground = R

= 11 KN.

8 0

2 years ago

I would love to stretch a wire from our house to the Shop so I can 'call' my husband in for meals. The wire could be tightened t

Semenov [28]

Note: I'm not sure what do you mean by "weight 0.05 kg/L". I assume it means the mass per unit of length, so it should be "0.05 kg/m".

Solution:
The fundamental frequency in a standing wave is given by
$f= \frac{1}{2L} \sqrt{ \frac{T}{m/L} }$
where L is the length of the string, T the tension and m its mass. If we plug the data of the problem into the equation, we find
$f= \frac{1}{2 \cdot 24 m} \sqrt{ \frac{240 N}{0.05 kg/m} }=1.44 Hz$

The wavelength of the standing wave is instead twice the length of the string:
$\lambda=2 L= 2 \cdot 24 m=48 m$

So the speed of the wave is
$v=\lambda f = (48 m)(1.44 Hz)=69.1 m/s$

And the time the pulse takes to reach the shop is the distance covered divided by the speed:
$t= \frac{L}{v}= \frac{24 m}{69.1 m/s}=0.35 s$

3 0

3 years ago