From Mechanics
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| | 4 (a) | | | 4 (a) |
| | [[Image:test2ans4.gif]] | | | [[Image:test2ans4.gif]] |
- | | 3 | + | | B1 |
- | | 4 | + | | (1 mark) |
- | | 5 | + | | B1: Correct force diagram |
| | | |
| |- | | |- |
| | 4 (b) | | | 4 (b) |
- | | 2 | + | | <math>\begin{align} |
- | | 3 | + | & 100a=200-980\sin 5{}^\circ \\ |
- | | 4 | + | & a=\frac{200-980\sin 5{}^\circ }{100}=1\textrm{.}15\ \text{m}{{\text{s}}^{-2}} \\ |
- | | 5 | + | \end{align}</math> |
| + | |
| + | | M1A1 |
| + | |
| + | M1 |
| + | |
| + | A1 |
| + | |
| + | | (4 marks) |
| + | | M1: Three term equation of motion |
| + | |
| + | A1: Correct equation |
| + | |
| + | M1: Rearranging equation. |
| + | |
| + | A1: Correct <math>a</math>. |
| + | |
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| |- | | |- |
| | 4 (c) | | | 4 (c) |
- | | 2 | + | | |
- | | 3 | + | <math>\begin{align} |
- | | 4 | + | & s=0\times 5+\frac{1}{2}\times 1\textrm{.}15\times {{5}^{2}} \\ |
- | | 5 | + | & =14\textrm{.}4\ \text{m} \\ |
| + | \end{align}</math> |
| + | |
| + | | M1 |
| + | |
| + | A1 |
| + | |
| + | A1 |
| + | |
| + | | (3 marks) |
| + | | M1: Using a constant acceleration equation |
| + | |
| + | A1: Correct equation |
| + | |
| + | A1: Correct distance. |
| + | |
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Revision as of 16:22, 19 January 2011
Solutions
1 (a)
| 44 .1=21 9.8t2t= 4.944.1=3 sORs=21 9.8 32=44.1AG Hits ground after 3 seconds | M1
A1
A1
(M1)
(A1)
(A1)
| (3 marks)
| M1: Use of constant acceleration
equation with v=0
A1: Correct equation
A1: Correct s
|
1 (b)
| v2=02+2 9.8 44.1v= 864.36=29 .4 ms−1ORv=0+9.8 3v=29.4 ms−1 | M1
A1
A1
| (3 marks)
| M1: Use of constant acceleration equation with v=0
A1: Correct equation.
A1: Correct v.
|
1 (c)
| Air resistance would slow the ball down.
| B1
| (1 mark)
| B1: Sensible statement about air resistance.
|
|
|
| (7 marks)
|
|
2 (a)
|
| B1
| (1 mark)
| B1: Correct horizontal forces.
Ignore any vertical forces.
|
2 (b)
| P=900N
| B1
| (1 mark)
| B1: Correct value for P.
|
2 (c)
| P−900=2000 1.2P=2400+900=3300N | M1
A1
A1
| (1 mark)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct P.
|
2 (d)
| 800−900=2000aa=2000−100=−0.05 ms−2Carisslowingdown | M1
A1
A1
A1
| (4 marks)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct a
A1: Correct statement
|
|
|
| (9 marks)
|
|
3 (a)
| R=20 9.8=196 N
| M1
A1
| (2 marks)
| M1: Use of R=mg
A1: Correct R.
|
3 (b)
| F=0.4 196=78.4 N
| M1
A1
| (2 Marks)
| M1: Use of \displaystyle F=\mu R
A1: Correct \displaystyle F.
|
3 (c)
| \displaystyle \begin{align}
& 100-78 \textrm{.}4=20a \\
& a=\frac{100-78 \textrm{.}4}{20}=1 \textrm{.}08 \text{ m}{{\text{s}}^{-2}} \\
\end{align}
| M1
A1
A1
| (3 marks)
| M1: Three term equation of motion
A1: Correct equation
A1: Correct \displaystyle a.
|
|
|
| (8 marks)
|
|
4 (a)
|
| B1
| (1 mark)
| B1: Correct force diagram
|
4 (b)
| \displaystyle \begin{align}
& 100a=200-980\sin 5{}^\circ \\
& a=\frac{200-980\sin 5{}^\circ }{100}=1\textrm{.}15\ \text{m}{{\text{s}}^{-2}} \\
\end{align}
| M1A1
M1
A1
| (4 marks)
| M1: Three term equation of motion
A1: Correct equation
M1: Rearranging equation.
A1: Correct \displaystyle a.
|
4 (c)
|
\displaystyle \begin{align}
& s=0\times 5+\frac{1}{2}\times 1\textrm{.}15\times {{5}^{2}} \\
& =14\textrm{.}4\ \text{m} \\
\end{align}
| M1
A1
A1
| (3 marks)
| M1: Using a constant acceleration equation
A1: Correct equation
A1: Correct distance.
|
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5 (a)
| 2
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| 5
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5 (b)
| 2
| 3
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| 5
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5 (c)
| 2
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