Answer:
d. less than 20m/s
Explanation:
To the 2nd car, the first car is travelling 10m/s east and 10m/s south. So the total velocity of the first car with respect to the 2nd car is
[tex]\sqrt{10^2 + 10^2} =10\sqrt{2}=14.14m/s
As 14.14m/s is less than 20m/s. d is the correct selection for this question.
Answer:
a=
Explanation:
The net force, 
of the box is expressed as a product of acceleration and mass hence
where m is mass and a is acceleration
Making a the subject, a= 
From the attached sketch,
∑ 
where 
is frictional force and 
is horizontal angle
Substituting ∑ as in the equation where we made a the subject
a= 
Since we’re given the value of F as 240N, as 41.5N, as 
and mass m as 30kg
a= 
Correct answer: D). Working Memory
The short term memory is the part of the memory system in which the information is stored for 30 seconds. However, it can be increased by rehearsal. Short term memory is also called active memory or the working memory. The working memory is the part of the cognitive system that is responsible for storing information temporarily for processing. It is important for reasoning.
Hence, the correct answer would be option D.
First make sure you draw a force diagram. You should have Fn going up, Fg going down, Ff going left and another Fn going diagonally down to the right. The angle of the diagonal Fn (we'll call it Fn2) is 35° and Fn2 itself is 80N. Fn2 can be divided into two forces: Fn2x which is horizontal, and Fn2y which is vertical. Right now we only care about Fn2y.
To solve for Fn2y we use what we're given and some trig. Drawing out the actual force of Fn2 along with Fn2x and Fn2y we can see it makes a right triangle, with 80 as the hypotenuse. We want to solve for Fn2y which is the opposite side, so Sin(35)=y/80. Fn2y= 80sin35 = 45.89N
Next we solve for Fg. To do this we use Fg= 9.8 * m. Mass = 30kg, so Fg = 9.8 * 30 = 294N.
Since the chair isn't moving up or down, we can set our equation equal to zero. The net force equation in the vertical direction will be Fn + Fn2y -Fg = 0. If we plug in what we know, we get Fn + 45.89 -294 = 0. Then solve this algebraically.
Fn +45.89 -294 = 0
Fn +45.89 = 294
Fn = 248.11 N
You'll get a more accurate answer if you don't round Fn2y when solving for it, it would be something along the lines of 45.88611 etc
Answer:
40 MJ (D)
Explanation:
Quantity of heat (Qh) = 100 MJ
temperature of steam (Th) = 450°c = 450 + 273 = 723 K
emperature of water (TI) = 20 °c = 20 + 273 = 293 k
efficiency = (Qh-Qi)/Qh = (Th-Ti)/Th
- Qi= 0.5947 x 
- (0.5947 x ) = Qi
Qi = 40.5 MJ equivalent to 40 MJ (D)
