# Search results

1. ### Finding net electric force

Homework Statement Given that q = 20 µC and d = 11 cm, find the direction and magnitude of the net electric force exerted on the point charge q1 below. Homework Equations F(elect) = k (q1,q2)/d^2 The Attempt at a Solution 1. after converting each unit to its appropriate form, F(net...
2. ### Chemistry Question -- Opening a valve between two containers...

Homework Statement Two closes containers are connected by a valve, which initially separates the containers from each other. C Container A has 8.00 L of H2 at 3.00 atm and temperature 400 k. Container B has 6.00 L of O2 at 4.00 atm and temperature 400 k The valve is opened, the gases mix, and...
3. ### Implicit function

Homework Statement The length ℓ, width w, and height h of a box change with time. At a certain instant the dimensions are ℓ = 4 m and w = h = 9 m, and ℓ and w are increasing at a rate of 1 m/s while his decreasing at a rate of 6 m/s. At that instant find the rates at which the following...
4. ### Finding time of a rocket

Homework Statement A model rocket takes off from ground level accelerating upward at a = 3.0 g. This upward acceleration lasts for a time τ = 15 s. Afterward the rocket continues upward, eventually stops rising, then falls back to the ground. How much time passes from the initial upward...
5. ### Vectors quantity

Homework Statement Vector A has magnitude A = 4.0 units and is directed θA = 15◦ counterclockwise from the positive x-axis. Vector B has magnitude B = 4.0 units and is directed θB = 85◦ counterclockwise from the positive x-axis. Determine the following quantity: |A + B|^2 − |A − B|^2...
6. ### Rotation acceleration

Homework Statement A disk of radius 16 cm rotating around a fixed axis at its center is accelerated from rest to an angular velocity of +13rev/min in +0.27 rev. (A )Find the angular acceleration (in rad/s^2), which is assumed to be constant, during this time interval. (B) what is the total...
7. ### Finding Magnitude

Homework Statement Two blocks are stacked one on top of the other with mass m1 on top and m1/m2= 3.0. There is no friction between m2 and the ground, but the coefficient of friction between m1 and m2 are given by μk= 0.40 and μs= 0.50. For what magnitudes of force acting horizontally on m1 do...
8. ### Finding Local Max and Min values and saddle in mult. Calculu

Homework Statement Find the local maximum and minimum values and saddle points of the function f(x,y) = x^2 + xy + y^2 + y Homework Equations Local max/min critical points saddle The Attempt at a Solution 1) partial derivative: fx = 2x+y fy = x+2y+1 from here, i'm a little confuse on...
9. ### Bullet Collision Question

Homework Statement A 6.64-g bullet is moving horizontally with a velocity of +340 m/s, where the sign + indicates that it is moving to the right. The bullet is approaching two blocks resting on a horizontal frictionless surface. Air resistance is negligible. The bullet passes completely through...
10. ### Uniform Circular Motion on a race track

Homework Statement On a banked race track, the smallest circular path on which cars can move has a radius of 116 m, while the largest has a radius of 153 m, as the drawing illustrates. The height of the outer wall is 11.6 m. Find (a) the smallest and (b) the largest speed at which cars can move...
11. ### Uniform Circular Motion of a centrifuge

Homework Statement A centrifuge is a device in which a small container of material is rotated at a high speed on a circular path. Such a device is used in medical laboratories, for instance, to cause the more dense red blood cells to settle through the less dense blood serum and collect at the...
12. ### Projectile Motion skateboarder

Homework Statement A skateboarder shoots off a ramp with a velocity of 5.30 m/s, directed at an angle of 52.0° above the horizontal. The end of the ramp is 1.40 m above the ground. Let the x axis be parallel to the ground, the +y direction be vertically upward, and take as the origin the point...
13. ### Motion in Space: Velocity and Acceleration

Homework Statement For V(t) = (1+t)i + (t^2-2t)j find: 1. velocity 2.Acceleration 3. speed/length 4. Unit Tangent 5. tangential component 6. normal component at t=2 Homework Equations The Attempt at a Solution 1. v'(t) = <1,2t-2> = <1, 2(t-1)> 2. a(t) = <0,2> 3. length = Square root of...
14. ### Vector Functions

Homework Statement (a) Sketch the plane with the given vector expression (b) find r'(t) (c) sketch the position vector r(t) and the tangent vector r'(t) for the given value of t r(t) = <t^2,t^3> t=1 Homework Equations The Attempt at a Solution 1) i derived the equation : r'(t) =...
15. ### Free fall physics velocity

Homework Statement While standing on a bridge 18.3 m above the ground, you drop a stone from rest. When the stone has fallen 2.50 m, you throw a second stone straight down. What initial velocity must you give the second stone if they are both to reach the ground at the same instant? Take the...
16. ### Finding Velocity

Homework Statement A car is traveling along a straight road at a velocity of +34.2 m/s when its engine cuts out. For the next 2.09 seconds, the car slows down, and its average acceleration is a1. For the next 6.49 seconds, the car slows down further, and its average acceleration is a2. The...
17. ### Finding the Nonzero Vector and Area of Triangle

Homework Statement Find a nonzero vector orthogonal to the plane through the point P, Q,and R. (b) also find the area of triangle PQR P(1,0,1) , Q(-2,1,3) , R(4,2,5) Homework Equations -Cross product -Finding the Angle -Area formula The Attempt at a Solution My steps: 1. i found the...
18. ### Dimensional Analysis

Homework Statement Using Dimensional Analysis, determine the value of (n) in the expressions for Q. The Equation: Q = pie R^n (p2-p1) / 8 ηL Homework Equations Given: [Q] = [L]^3 / [T} [L] = [L] [R] = [L] [p2 and p1] = [M] / {[L][T]^2} [η] = [M] / {[L][T]} pie, 8, and...
19. ### Macclaurin Series

Homework Statement Find the Maclaurin series for f(x)=(1-x)^-2 using the definition of a Macluarin series,[ Assume that f has a power series expansion. Also find Homework Equations Maclaurin Series The Attempt at a Solution Steps: 1) I found the first 3 derivative of the function 2) I...
20. ### Finding the sum of a Series that is converge or Diverge

Homework Statement Determine whether the series is either Converge or Diverge, if it's convergent, find its sum ∑ from n=1 to ∞ of (1+2^n)/(3^n) Homework Equations The Attempt at a Solution Steps: 1) i replaced the (1+2^n) to just (2^n) and my equation behaves like ∑ (2/3)^n...
21. ### 1-D kinematic Problem

I'm confuse by what the question is asking as far as the conversion (km/hr/s). Can any please help me? Homework Statement A jumbo jet must reach a speed of 240 km/hr on the runway for takeoff. What is the minimum constant acceleration (in km/hr/s) needed for takeoff from a 1.34 km runway...