Pre calc problem?
this is a wave type function first we need to get everything into MKS units the velocity is 10000m/3600 s which is 2.77 m/s with a diameter of of .7 meters the angular velocity is 3.957 radians/sec so the equation starts as .2*sin(3.957 t+p)+x now since the reflector starts at its highest point which would coincide as sine(Pi/2) we know that p=Pi/2 this means we can write the equation as .2*sin(3.957 t+Pi/2)+x or .2*cos(3.957 t)+x the next thing to find is the value of x which is what identifies that the reflector never touches the ground now when 20*sin(3.957 t+Pi/2)=0 then the reflector will be at equall height as the center of the wheel which, since the wheel is .7 m in diameter, means that x=.35 so your solution is 20*sin(3.957 t+Pi/2)+.35 [meters] or 20*sin(3.957 t+)+.35 [meters]
Distance problems...precalculus. please help!!?
1. A college crew team can maintain a speed equal to 15km/hr in still water. If it takes them 50 mins to row 6 km. upstream and 6 km. back, what is the rate of the current of the river? 2. Bob rode his bike at a speed of 15mph and returned the same route at 10mph. If the entire trip took 7.5 hours, how far was his total trip? thanks so much!!
Distance problems...precalculus. please help!!?
1. Distance is the same, and distance = speed x time in both cases But you're missing the time it took to come back! I'll assume you said 30 minutes so you can see the calculation. Note the speed is per hour, so your times must be too. s = vt v1t1 = v2t2 (15 - x)(50/60) = (15 + x)(30/60) 50(15 - x) = 30(15 + x) 750 - 50x = 450 + 30x 750 - 450 = 40x + 30x 300 = 70x x = 300/70 = 4.2857... km/hr 2. Same principle as before: 15t1 = 10t2 t1 + t2 = 7.5 t1 = 7.5 - t2 15(7.5 - t2) = 10t2 112.5 - 15t2 = 10t2 112.5 = 10t2 + 15t2 112.5 = 25t2 t2 = 112.5 / 25 = 4.5 It took 4.5 hours to return at 10mph, so he travelled (4.5 * 10) = 45 miles each way, which is 90 miles in total.
Help With Math Precalculus?
The circumference of the wheel is 2*pi*33 cm That's the distance the bike goes with each revolution To go at 25km/hr, it must rotate at 25*10^5/(2*pi*33) revolutions per hour (100 cm per metre, 1000 metres per km) 25*10^5/(2*pi*33*60) revolutions per per minute The rear sprocket rotates at the same speed That works out at 200.95 rpm The ratio of rear sprocket radius to front sprocket radius must be 95/200.95 Thus the rear sprocket radius must be 7*95/200.95 = 3.31 cm <<<<
How do I calculate EMI on bike loan?
The mathematical formula for calculating EMIs is:EMI = [P x R x (1+R)^N]/[(1+R)^N-1], where P stands for the loan amount or principal,R is the interest rate per month [if the interest rate per annum is 11%, then the rate of interest will be 11/(12 x 100)],and N is the number of monthly installments.EMI Calculator (for calculating Home loans, Personal loans, Bike loans and Car loans) works on the basis of this formula.Source: http://emicalculators.in/
Pre-Calc Rate Word Problem...How Fast Did He Ride...?
v[b] = speed of the bike v[w] = speed of walking v[b] * (1/2) + v[w] * (3 - 1/2) = 15 v[b] = 4 * v[w] , therefore v[w] = (1/4) * v[b] v[b] * (1/2) + (1/4) * v[b] * (5/2) = 15 v[b] * ((1/2) + (1/4) * (5/2)) = 15 v[b] * (1/2) * (1 + 5/4) = 15 v[b] * (9/4) = 30 v[b] = 120 / 9 v[b] = 40/3 The bike travels at 13.333 mph
Pre-Calculus Help something with a bicycle pedal and wheel!!!?
The key here is that the linear velocity of the chain must be the same on both sprockets. 30 rpm = angular velocity of 60pi radians/min; linear velocity = radius* angular velocity = 240pi inches/min. Working backward on the 2" sprocket, we get an angular velocity of 120pi radians/min which equals 60 rpm. The bicycle tire is also rotating at 60 rpm which equals 120pi radians per minute which equals a linear velocity of 120pi*13 = 1560pi inches/min. If you want the speed in miles per hour 1560pi inches/min(60min/hour)(1ft/12inches)(1mi... = 4.64 mph.
If u r good with pre-calc., can u help me find this equation?
The reflector makes a revolution every 1.25 seconds, which means it has an angular velocity of 288 degrees/s, or 8*pi/5 radians/s. If you establish the convention that the 0/2 PI mark is at the very top of the wheel (so the PI mark is at the very bottom, the lowest point of the reflector), then you can easily calculate that the reflector's starting position was 36 degrees past vertical (it moved 144 degrees in 0.5 seconds to PI). Since the wheel is 76 cm in diameter, the reflector is 23 cm from the center (38 - 15 = 23) and the center is 38 cm from the ground, the respective values of a and k in the equation. The time offset, h, is 0.125 seconds because that's how much time it takes the wheel to travel 36 degrees, the amount of the reflector's "head start." If you combine these facts with the above angular speed of the reflector, then you should end up with this equation: y = 23 cos [8*PI*(t + 0.125)/5] + 38 y(0) = 23 cos 36 + 38 ~ 56.6074 cm (starting height) y(0.5) = 23 cos 180 + 38 = 15 cm (relector's LOWEST pt.) y(1.125) = 23 cos 360 + 38 = 61 cm (reflector's HIGHEST pt.) Remember, the reflector makes a complete revolution every 1.25 seconds, so..... Reflector is at lowest point at t = 0.5, 1.75, 3, etc. Reflector is at highest point at t = 1.125, 2.375, 3.625, etc. P.S. The first person's answer gives values for y that are flat out impossible in light of the problem's given information, but I hope that I've been of some help.
Can someone help me solve an math application problem?
Let: B = Bicycle speed = 8 mph C = Car speed, mph Formula: Distance traveled = Speed * Time traveling Speed = (Distance traveled) / (Time traveling) By the time the car overtakes the bicycle, they would have traveled the same distance. By this time, the bicycle would have traveled for 1 hour and 15 minutes or 1.25 hours; the car would have traveled for 15 minutes or 0.25 hours Distance traveled by bicycle: 8 mph(1.25 hours) = 10 miles Distance traveled by car when it overtakes the bicycle: 10 miles Required car speed: C = (Distance traveled by car) / (Time traveling) C = 10 miles / 0.25 hours C = 40 mph Answer: Therefore, the father must drive the car at 40 mph to overtake his son's bicycle in 15 minutes. ALTERNATIVE SOLUTION: Equation: B(1.25) = C(0.25) Solution: C = B(1.25) / 0.25 C = 8(1.25) / 0.25 C = 40
Help. This is my pre-calc hm and i really need help to raise my grade! If possible, do a sinusoidal graph.?
Lamaj rode his bike over a piece of gum. At time t=1.25 sec. the gum was at a max height above the ground, 1 sec later it was at a min. If the wheel diameter is 68 cm, find the trigonometric equation that will find the height of the gum in cm at any time t.