Phoebe's insulated foam cup is filled with 0.15 kg of coffee (mostly water) that is too hot to drink, so she adds

In a chemical equation, numbers often appear in front of a chemical formula. What do these numbers indicate?

solong [7]

The number of molecules in each atom in the reaction.

5 0

3 years ago

How do we know that an object has accelerated?

Olin [163]

A change in velocity or a change in direction, or both! Hope this helps

7 0

3 years ago

A steel plate weighing 180 lb with center of gravity at point G is supported by a roller at point A, a bar DE, and a horizontal

melamori03 [73]

Answer:

Therefore, the force supported by the hydraulic cylinder is = -70.01 lb

Thus, the force supported by the bar = -233.84 lb

The reaction force supported by the reaction of the roller = 341.31 lb

Explanation:

The attached diagrams is shown in the file below:

From there; taking moments about point A

$\sum M__A }=0$

- 40 (180) - (80) $F_E$ Cos 37° + 55

-7200 + $F_E$ (-80 Cos 37° + 55 sin 37° ) = 0

= - 7200 - 30.79 $F_E$

- 30.79 $F_E$ = 7200

$F_E$ = $-\frac{7200}{30.79}$

$F_E$ = -233.84 lb

Thus, the force supported by the bar = -233.84 lb

Taking the equilibrium of forces in the vertical direction

$\sum f_y = 0$

$F_E$ sin 37 + $F_A$ cos 20 - $F_G$ = 0

- 233.84 sin 37 + $F_A$ cos 20 - 180 = 0

$F_A$ cos 20 = 320.73

$F_A$ = $\frac{320.73}{cos 20}$

$F_A$ = 341.31 lb

The reaction force supported by the reaction of the roller = 341.31 lb

Taking the equilibrium of forces on the horizontal direction.

$\sum f_y = 0$

$F_E$ cos 37 - $F_{CB} + F_A$ sin 20° = 0

-233.84 cos 37 - $F_{CB}$ + 341.31 sin 20° = 0

-186.75 - $F_{CB}$ + 116.74 = 0

- $F_{CB}$ -70.01 = 0

- $F_{CB}$ = 70.01

$F_{CB}$ = - 70.01 lb

Therefore, the force supported by the hydraulic cylinder is = -70.01 lb

7 0

4 years ago

A ball bearing is projected vertically upwards from the ground with a velocity of 15ms. Calculate the time taken by the ball to

cupoosta [38]

Answer:

t = 3 [s]

Explanation:

To solve this problem we must use the following equation of kinematics.

$v_{f}=v_{o}-g*t$

where:

Vf = final velocity [m/s]

Vo = initial velocity = 15 [m/s]

g = gravity acceleration = 10 [m/s²]

t = time [s]

Now replacing we have:

$0 = 15 -10*t\\10*t=15\\t= 1.5[s]$

Note: In the equation above the gravity acceleration is negative, because the movement of the ball bearing is pointing againts the gravity acceleration.

The time calculated is only when the ball bearing reaches the highest elevation, and it will take the same time for descending, therefore the total time is:

t = 1.5 + 1.5 = 3 [s]

7 0

3 years ago

A 70kg car drives through a curve with radius 50m. What is the minimum angle the road should be tilted to keep the car on the ro

worty [1.4K]

when car moves along a circular path then centripetal force for taking turn will be provided by the component of normal force

Let the road is tilted by some angle

so force equations are given as

$F_n cos\theta = mg$