How a 300-n force can combine with a 100-n force to produce a net force of 200n on a sled?

Explain how would you identify an unknown substance

arsen [322]

Find out what the substance is

7 0

3 years ago

A block is hung by a string from the inside roof of a van. when the can goes straight ahead at a speed of 28 m/s, the block hang

Elis [28]

Answer:

θ =28.07⁰

Explanation:

when van moves around an unbanked curve, horizontal component of normal force is equal to centripetal force

$F_{c}= F_{n} sin\theta$

$F_{n}sin\theta= \frac{mv^{2} }{r}$ ---(1)

There is no motion in vertical direction, so vertical component of normal force is balanced with weight of block i.e.

$F_{n}cos\theta= mg$ ----(2)

divide (1) and (2)

$\frac{F_{n}sin\theta}{F_{n}cos\theta} = \frac{\frac{mv^{2} }{r} }{mg}$

$tan \theta=\frac{v^{2} }{rg}$

$\theta=tan^{-1} \frac{v^{2} }{rg}$

v = 28 m/s

r = 150 m

g = 9.8m/ $s^{2}$

θ = 28.07⁰

5 0

3 years ago

Venus has an average distance to the sun of 0.723 AU. In two or more complete sentences, explain how to calculate the orbital pe

Mice21 [21]

As per the question the distance of venus from sun is given as 0.723 AU

We have been asked to calculate the time period of the planet venus.

As per kepler's laws of planetary motion the square of time period of planet is directly proportional to the cube of semi major axis. mathematically

$T^{2} \alpha R^{3}$

⇒ $T^{2} = KR^{3}$ where is k is the proportionality constant

We may solve this problem by comparing with the time period of the earth . We know that time period of earth is 365.5 days

Hence $T_{1} =365.5 days$

The distance of sun from earth is taken as 1 AU i.e the mean distance of earth from sun

Hence $R_{1} =1 AU$

The distance of venus from sun is 0.723 AU i.e $R_{2} =0.723$

From keplers law we know that- $\frac{T_{1} ^{2} }{T_{2} ^{2} } =\frac{R_{1} ^{3} }{R_{2} ^{3} }$

⇒ $T_{2} ^{2} =T_{1} ^{2} *\frac{R_{2} ^{3} }{R_{1} ^{3} }$

Putting the values mentioned above we get-

$T_{2} ^{2} =50,350.132851075$

⇒ $T_{2} =\sqrt{50,350.132851075}$

⇒ $T_{2} = 224.388352752710 days.$

Hence the time period of venus is 224.388352752710 days

7 0

4 years ago

Read 2 more answers

Worldâs tallest building. suppose that you drop a marble from the top of the burj khalifa building in dubai, which is about 830

-Dominant- [34]

<span>a) 13 seconds b) 130 m/s The formula for the distance an object moves while under constant acceleration is d = 1/2AT^2. So let's define d as 830 m, A as 9.8m/s^2, and solve for T 830 m = 1/2 9.8 m/s^2 T^2 830 m = 4.9 m/s^2 T^2 Divide both sides by 4.9 m/s^2 169.3878 s^2 = T^2 Take the square root of both sides 13.01491 s = T Since we only have 2 significant figures, round the result to 13 seconds which is the answer to the first part of the question. To find out how fast the marble is moving, just multiply T and A together 13 s * 9.8 m/s^2 = 127.4 m/s Since we only have 2 significant figures, round the result to 130 m/s.</span>

7 0

4 years ago

A ball is thrown upward with a speed of 28.2 m/s.A. What is its maximum height?B. How long is the ball in the air?C. When does t

Ede4ka [16]

Answer:

(A) The maximum height of the ball is 40.57 m

(B) Time spent by the ball on air is 5.76 s

(C) at 33.23 m the speed will be 12 m/s

Explanation:

Given;

initial velocity of the ball, u = 28.2 m/s

(A) The maximum height

At maximum height, the final velocity, v = 0

v² = u² -2gh

u² = 2gh

$h = \frac{u^2}{2g}\\\\h = \frac{(28.2)^2}{2*9.8}\\\\h = 40.57 \ m$

(B) Time spent by the ball on air

Time of flight = Time to reach maximum height + time to hit ground.

Time to reach maximum height = time to hit ground.

Time to reach maximum height is given by;

v = u - gt

u = gt

$t = \frac{u}{g}$

Time of flight, T = 2t

$T = \frac{2u}{g}\\\\ T = \frac{2*28.2}{9.8}\\\\ T = 5.76 \ s$

(C) the position of the ball at 12 m/s

As the ball moves upwards, the speed drops, then the height of the ball when the speed drops to 12m/s will be calculated by applying the equation below.

v² = u² - 2gh

12² = 28.2² - 2(9.8)h

12² - 28.2² = - 2(9.8)h

-651.24 = -19.6h

h = 651.24 / 19.6

h = 33.23 m

Thus, at 33.23 m the speed will be 12 m/s

6 0

3 years ago